Alcohol acetyltransferase genes and use thereof

ABSTRACT

This invention disclosed herein provides an alcohol acetyl transferase (&#34;AATase&#34;), an AATase encoding gene and a yeast having an improved ester producing ability due to transformation with the AATase encoding gene. This invention also provides a process for producing an alcoholic beverage having an enriched ester flavor using the transformed yeast.

This application is a divisional of application Ser. No. 08/077,939,filed on Jun. 18, 1993 now U.S. Pat. No. 5,521,088.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an alcohol acetyltransferase ("AATase")produced by, for example, Saccharomyces cerevisiae, a DNA sequenceencoding, i.e., having an ability for biotechnologically producing,AATase, and a yeast having an improved ester producing ability due tothe transformation with the DNA sequence. The present invention alsorelates to a process for producing an alcoholic beverage having anenhanced ester flavor.

2. Related Art

It is well known that acetate esters affect the flavor quality ofalcoholic beverages such as sake, beer, wine and whisky. These estersare in general present in the fermented supernatant, because yeastproduces a various kinds of alcohols which are further converted intoesters during a fermentation procedure.

In particular, isoamyl acetate is an ester which provides a good fruityflavor for alcoholic beverages. It has been suggested that the ratio ofisomyl acetate to isoamyl alcohol, which is a precursor of isomylacetate, is closely related to the evaluation value of the sensary test.For example, sake having a great ratio of isomyl acetate to isoamylalcohol valued as "Ginjo-shu" in the sensary test (JOHSHI HOKOKU, No.145, P. 26 (1973).

As previously reported by Yoshioka et al., Agric. Biol. Chem., 45, 2188(1981), AATase is an enzyme which plays primary role in the productionof isoamyl acetate. The AATase synthesizes isoamyl acetate by thecondensation of isoamyl alcohol and acetyl-CoA. Furthermore, AATase hasbeen known to have a wide substrate specificity and to produce manyacetate esters such as ethyl acetate in the same mechanism as describedabove.

Therefore, in order to increase the esters, such as isoamyl acetate inthe alcoholic beverages, it is effective to enhance the AATase activityof a yeast. Some of the conventional consideration in the production ofthe alcoholic beverages, for example, selecting raw materials orcontrolling fermentation conditions, as a result, have enhanced theactivity of the AATase.

However, though it has been well known that AATase is important enzymefor the production of esters, there are few reports referring. to theAATase. Partial purifications of the enzyme have been described in somereports (for example, NIPPON NOGEI KAGAKUKAISHI, 63, 435 (1989); Agric.Biol. Chem., 54, 1485 (1990); NIPPON JOZO KYOKAISHI, 87, 334 (1992),but, because AATase has very labile activity, complete purification ofAATase, and the cloning of the gene encoding AATase has not beenreported, so far.

SUMMARY OF THE INVENTION

An object of the present invention is to reveal the structure of AATaseand isolate the AATase gene, thereby to obtain a transformed yeasthaving an enhanced AATase producing ability and to produce an alcoholicbeverage having an enhanced ester flavor.

According to the first embodiment of the present invention, the presentinvention provides an AATase originated from yeast having an ability fortransferring the acetyl group from acetyl-CoA to an alcohol to producean acetate ester and having a molecular weight of approximately 60,000by SDS-PAGE.

According to the second embodiment of the present invention, the presentinvention provides an AATase comprising a polypeptide selected from agroup consisting of:

(1a) a polypeptide having an amino acid .sequence from A to B of theamino acid sequence (SEQ ID NO:15) (SEQ ID NO:19 or residue 19-525 ofSEQ ID NO:19) shown in FIG. 1;

(1b) a polypeptide having an amino acid sequence from A to B of theamino acid sequence (SEQ ID NO:17) shown in FIG. 2; and

(1c) a polypeptide having an amino acid sequence from A to C or B to C(SEQ ID NO:19 or residue 19-525 of SEQ ID NO:19) of the amino acidsequence shown in FIG. 17.

According to the third embodiment of the present invention, the presentinvention provides the AATase encoding gene having a DNA sequenceselected from a group the consisting of:

(2a) a DNA sequence encoding a polypeptide having an amino acid sequencefrom A to B of the amino acid sequence (SEQ ID NO:15) shown in FIG. 1;

(2b) a DNA sequence encoding a polypeptide having an amino acid sequencefrom A to B of the amino acid sequence (SEQ ID NO:17) shown in FIG. 2;and

(2c) a DNA sequence encoding a polypeptide having an amino acid sequencefrom A to C or B to C (SEQ ID NO:19 or residue 19-525 of SEQ ID NO:19)of the amino acid sequence shown in FIG. 17.

According to the fourth embodiment of the present invention, the presentinvention provides a DNA sequence comprising an AATase gene selectedfrom a group consisting of:

(3a) an AATase gene having a DNA sequence from A to B (bases 233-1808 ofSEQ ID NO:14) of the DNA sequence shown in FIG. 1;

(3b) an AATase gene having a DNA sequence from A to B (bases 346-1920 ofSEQ ID NO:16) of the DNA sequence shown in FIG. 2;

(3c) an AATase gene having a DNA sequence from A to C or B to C (bases311-1885 or 365-1885 SEQ ID NO:18) of the DNA sequence shown in FIG. 17;and

(3d) a DNA sequence which hybridizes with any one of genes (3a) to (3c).

According to the fifth embodiment of the present invention, the presentinvention provides a transformed yeast having an enhanced AATaseproducing ability due to the transformation using the AATase geneselected from (2a) to (2c) or a DNA sequence selected from (3a) to (3d).

According to the sixth embodiment of the present invention, the presentinvention provides a process for producing a alcoholic beverage havingan enriched ester flavor using a transformed yeast as described above.

According to the seventh embodiment of the present invention, thepresent invention provides a method for isolating a DNA sequenceencoding AATase, comprising the steps of:

(a) preparing a DNA fragment having a length of at least 20 bases of aDNA sequence which encodes a polypeptide having an amino acid sequencefrom A to B (SEQ ID NO:15) of the amino acid sequence shown in FIG. 1;

(b) preparing a gene library which has been made from DNA strands havinga substantially same length in the range from 5×10³ to 30×10³ basesobtained by cutting the chromosome of a yeast;

(c) cloning a DNA fragment by hybridization from gene library of (b),using the DNA fragment of (a) as a probe.

The terms "DNA fragment" "DNA sequence" and "gene" are herein intendedto be substantially synonymously.

Since the AATase gene have been obtained, a yeast can be transformedusing this gene as a foreign gene by a genetic engineering method. Thatis, the gene can be transfected into a yeast cell as a extranuclearand/or intranuclear gene to afford the yeast an AATase producing abilitygreater than that of the host cell, and using these transformants analcoholic beverage having the enriched ester flavor can be made.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1(a) and (b) show an amino acid sequence (SEQ ID NO:15) of AATaseand DNA sequence (SEQ ID NO:14) of the AATase encoding gene according tothe present invention;

FIGS. 2(a) and (b) show a amino acid sequence (SEQ ID NO:17) of AATaseand DNA sequence (SEQ ID NO:16) of another AATase encoding geneaccording to the present invention;

FIG. 3 shows a restriction map of the AATase encoding gene originatedfrom a sake yeast according to the present invention;

FIG. 4 shows two restriction maps of the AATase originated from abrewery lager yeast according to the present invention;

FIG. 5 shows a restriction map of the AATase originated from a wineyeast according to the present invention;

FIG. 6 shows the process for preparing the probe used for obtaining theAATase gene from the wine yeast (SEQ ID NOS 12 and 13 correspond toPrimers A and B, respectively);

FIG. 7 shows the elution profile of an AATase active fraction by theaffinity chromatography method among the purification processesaccording to the present invention;

FIG. 8 shows an SDS-polyacrylamide electrophoresis of the AATase activefraction eluted by the affinity chromatography according to the presentinvention;

FIG. 9 shows the substrate specificity of the AATase according to thepresent invention to a variety of alcohols;

FIG. 10 shows a restriction map of the expression vector YEp13K foryeast;

FIG. 11 shows a restriction map of the expression vector YATK11 havingthe AATase gene originated from a sake yeast according to the presentinvention;

FIG. 12 shows a restriction map of the expression vector YATL1 havingthe AATase 1 gene originated from a brewery lager yeast according to thepresent invention; FIG. 13 shows a restriction map of the expressionvector YATL2 having the AATase 2 gene originated from a brewery lageryeast according to the present invention;

FIG. 14 shows a restriction map of the sake-yeast expression vectorYATK11G having the AATase gene originated from a sake yeast according tothe present invention;

FIG. 15 shows a restriction map of the brewery lager yeast vector YATL1Ghaving the AATase 1 gene originated from a brewery lager yeast accordingto the present invention;

FIG. 16 shows a part of the brewery lager yeast expression vectorconstruction; and

FIGS. 17(a)-(f) shows the amino acids (SEQ ID NO:19) and DNA sequence(SEQ ID NO:19) of the brewery lager yeast AATase 2 gene according to thepresent invention.

DETAILED DESCRIPTION OF THE INVENTION

AATase

AATase, alcohol acetyltransferase, is an enzyme having an ability forproducing an acetate ester by transferring the acetyl group fromacetyl-CoA to alcohols.

The alcohols herein primarily mean alcohols having straight or branchedchains having 1 to 6 carbon atoms. According to our studies, however, ithas been found that the AATase may employ as substrates alcohols havinga higher number of carbon atoms such as 2-phenyl ethylalcohol.

Thus, "the alcohols" should be construed to include a wide range ofalcohols, if it is necessary to discuss the substrate alcohol of theAATase in the present invention.

The AATase according to the present invention is originated from yeast.The AATase is specifically obtained from Saccharomyces cerevisiae and isa polypeptide having any one of the polypeptides (1a)-(1c) definedabove. Specifically, the polypeptide includes a polypeptide having anamino acid sequence from A to B (SEQ ID NO:15) of the amino acidsequence shown in FIG. 1; a polypeptide having an amino acid sequencefrom A to B (SEQ ID NO:17) of the amino acid sequence shown in FIG. 2; apolypeptide having an amino acid sequence from A to C (SEQ ID NO:19) ofthe amino acid sequence shown in FIG. 17; and a polypeptide having anamino acid sequence from B to C (residues 19-525 of SEQ ID NO:19) of theamino acid sequence shown in FIG. 17. Furthermore, it has been clarifiedby genetic engineering for protein engineering that the physiologicalactivity of a polypeptide may be maintained with the addition,insertion, elimination, deletion or substitution of one or more of theamino acids of the polypeptide. The polypeptide therefore include amodified polypeptide of any one of the above polypeptides due to theaddition, insertion, elimination, deletion or substitution of one ormore of amino acid of the polypeptide so long as the modifiedpolypeptide has an AATase activity.

Saccharomyces cerevisiae used herein is a microorganism described in"The yeast, a taxonomic study", the 3rd Edition, (ed. by N. J. W.Kreger-van Rij, Elsevier Publishers B. V., Amsterdam (1984), page 379),or a synonym or mutant thereof.

AATase and its purification method have been reported in some papers,for instance, NIPPON NOGEIKAGAKU KAISHI, 63, 435 (1989); Agric. Biol.Chem., 54, 1485 (1990); NIPPON JOSO KYOKAISHI, 87, 334 (1992). However,so far as the present inventors know, the AATase has not been purifiedto homogeneity, so its amino acid sequence has not been determined.

The present inventors have now found that an affinity column with1-hexanol as a ligand can be used successfully for purifying the AATase.We have thus completely purified the AATase from Saccharomycescerevisiae by use of this affinity column and defined some properties ofthe enzyme. The amino acid sequence shown in FIG. 1 (SEQ ID NO:15) isobtained by analysis of the AATase originated from Saccharomycescerevisiae which has thus purified to homogenity.

The typical property of the AATase which have been defined according tothe present invention includes the molecular weight of the AATase.Although the molecular weight of the AATase previously reported is inthe range from 45,000 to 56,000, the molecular weight of the AATasepurified according to the present invention is approximately 60,000 bySDS-polyacrylamide gel electrophoresis (SDS-PAGE), suggesting that it isdifferent from the protein reported previously. The molecular weight ofthe AATase deduced from the DNA sequence was ca. 61,000.

The AATase of the present invention has enzymological andphysicochemical properties as set forth below.

(a) Action:

This enzyme acts on a variety of alcohol such as ethyl alcohol andacetyl-CoA to produce an acetate ester.

(b) Substrate specificity:

This enzyme acts on various kinds of alcohol having 2 to 5 carbon atoms,more efficiently on alcohols having 2 to 5 carbon atoms. In addition,the enzyme acts more efficiently on straight chain alcohols ratherbranched chain alcohols.

(c) Molecular weight: ca. 60,000

(d) Optimum and stable pH:

optimum pH: 8.0,

stable pH: 7.5-8.5

(e) Optimum and stable temperature:

optimum temperature: 25° C.,

stable temperature: 4° C.;

(f) Inhibitors:

This enzyme is intensively inhibited by parachloromercury benzoate(PCMB) and dithiobisbenzoic acid (DTNB);

(g) Effects of various fatty acids on the activity:

This enzyme is not noticeably inhibited by a saturated fatty acid butintensively inhibited by an unsaturated fatty acid;

(h) Km value to isoamyl alcohol and acetyl-CoA:

isoamyl alcohol: 29.8 mM,

acetyl CoA: 190 μM.

The AATase can be obtained by a procedure comprising culturing yeastcells of Saccharomyces cerevisiae KYOKAI No. 7 and recovering andpurifying the crude enzyme from the content of the organism as describedin Examples below.

DNA sequence or DNA fragment/gene which produces AATase

In the present invention, the DNA sequence or DNA fragment having anability of producing AATase means the DNA sequence or DNA fragment whichcodes for a polypeptide having AATase activities. The amino acidsequence of a polypeptide encoded by the sequence or fragment, i.e., theAATase, is selected from the group consisting of the following(2a)-(2c), and is specifically selected from the group consisting of thefollowing (3a)-(3d):

(2a) a DNA sequence encoding a polypeptide having an amino acid sequencefrom A to B (SEQ ID NO:15) of the amino acid sequence shown in FIG. 1;

(2b) a DNA sequence encoding a polypeptide having an amino acid sequencefrom A to B (SEQ ID NO:17) of the amino acid sequence shown in FIG. 2;

(2c) a DNA sequence encoding a polypeptide having an amino acid sequencefrom A to C or B to C (SEQ ID NO:19 or residues 19-525 of SEQ ID NO:19)of the amino acid sequence shown in FIG. 17.

(3a) an AATase gene having a DNA sequence from A to B (bases 233-1808 ofSEQ ID NO:14) of the DNA sequence shown in FIG. 1;

(3b) an AATase gene having a DNA sequence from A to B (bases 346-1920 ofSEQ ID NO:16) of the DNA sequence shown in FIG. 2;

(3c) an AATase gene having a DNA sequence from A to C or B to C (bases311-1885 of SEQ ID NO:18) of the DNA sequence shown in FIG. 17; and

(3d) a DNA sequence capable of hybridizing with any one of genes (3a) to(3c).

The DNA sequence varies depending upon the variation of the polypeptide.In addition, it is well known by one skilled in the art that a DNAsequence is easily defined according to the knowledge referring to theso called "degeneracy", once an amino acid sequence is given. Thus, oneskilled in the art can understand that certain codons present in thesequence shown in FIGS. 1, 2 and 17 can be substituted by other codonsand produce a same polypeptide. This means that the DNA sequence (or DNAfragment) of the present invention includes DNA sequences which encodethe same peptide but are different DNA sequences in which codons in thedegeneracy relation are used. Furthermore, one skilled in the art canunderstand that the DNA sequence of the present invention include theDNA sequence which encodes a modified polypeptide oK any of one of thepolypeptides (1a) to (1c ) due to the addition, insertion, elimination,deletion or substitution of one or more amino acid of thesepolypeptides. In this connection, the term "encoding" is synonymous withthe term "capable of encoding".

The DNA sequence of the present invention may be obtained from a naturalgene source or obtained by total synthesis or semi-synthesis (i.e.,synthesized with use of a part of a DNA sequence originated from anatural gene source).

Form the natural gene source, the DNA sequence of the present inventioncan be obtained by conducting DNA manipulations such as plaquehybridization, colony hybridization and PCR process using a probe whichis a part of a DNA sequence producing the AATase of the presentinvention. These methods are well-known to one skilled in the art andcan be easily performed.

Suitable gene sources for obtaining a DNA sequence having an AATaseproducing ability by these methods include for example bacteria, yeastand plants. Among these gene sources, yeast which is currently used forthe production of fermentation foods such as sake and soy sauce is oneof the best candidate having a DNA sequence of the present invention.

The typical form of the DNA sequence of the present invention is apolypeptide which has a length just corresponding to the length ofAATase. In addition, the DNA sequence of the present invention may havean additional DNA sequences which are bonded upstream and/or downstreamthe sequence. A specific example of the latter is a vector such asplasmid carrying the DNA sequence of the present invention.

Suitable example of the DNA sequence of the present invention is from Ato B of the amino acid sequence shown in FIG. 1. (bases 233-1808 of SEQID NO:14) This sequence is obtained by analyzing an AATase encoding geneobtained from a yeast strain, SAKE YEAST KYOKAI No. 7.

Transformation

The procedure or method for obtaining a transformant is commonly used inthe field of genetic engineering. In addition to the method describedbelow, any conventional transformation method (for example, AnalyticalBiochemistry, 163, 391 (1987)), is useful to obtain the transformant.

Vectors which can be used include all of the known vectors for yeastsuch as YRp vectors (multicopy vectors for yeast containing the ARSsequence of the yeast chromosome as a replication origin), YEp vectors(multicopy vectors for yeast containing the replication origin of the 2μm DNA of yeast), YCp vectors (single copy vectors for yeast containingthe DNA sequence of the ARS sequence of the gene chromosome. and the DNAsequence of the centromere of the yeast chromosome), YIp vectors(integrating vectors for yeast having no replication origin of theyeast). These vectors is well-known and described in "GeneticEngineering for the Production of Materials", NIPPON NOGEI KAGAKUKAI ABCSeries, ASAKURA SHOTEN, p. 68, but also can be easily prepared.

In addition, in order to express the gene of the DNA sequence accordingto the present invention or to increase or decrease the expression, itis preferable that the expression vector contains a promoter which is aunit for controlling transcription and translation in the 5'-upstreamregion and a terminator in the 3'-downstream region of the DNA sequence.Suitable promoters and terminators are for example those originated fromthe AATase gene itself, those originated from any known genes such asalcohol dehydrogenase gene (J. Biol. Chem., 257, 3018 (1982)),phosphoglycerate kinase gene (Nucleic Acids Res., 10, 7791 (1982)) orglycerolaldehyde-3-phosphate dehydrogenase gene [J. Biol. Chem., 254,9839 (1979)) or those which are the artificial modifications of theformer.

The yeast to be transformed in the present invention, i.e. the hostyeast, may be any yeast strain which belongs taxonomically to thecategory of yeast, but for the purpose of the present invention, a yeaststrain for producing alcoholic beverages which belongs to Saccharomycescerevisiae such as brewery yeast, sake yeast and wine yeast arepreferred. Suitable examples of yeast include brewery yeast such as ATCC26292, ATCC 2704, ATCC 32634 and AJL 2155; sake yeast such as ATCC 4134,ATCC 26421 and IFO 2347; and wine yeast such as ATCC 38637, ATCC 38638and IFO 2260.

Another group preferred as the host yeast is baker's yeast such as ATCC32120.

Preparation of Alcoholic Beverages

The transformed yeast having an enhanced AATase producing ability isprovided with a character intrinsic to the host yeast as well as theintroduced character. The transformant thus can be used for variousapplications focussed to the intrinsic character.

If the host yeast is a yeast for preparing alcoholic beverages, thetransformed yeast also has an ability for fermenting saccharides toalcohols. Therefore, the transformed yeast according to the presentinvention provides an alcoholic beverages having an enhanced or enrichedester flavor.

Typical alcoholic beverages include sake, wine, whiskey and beer. Inaddition, the process for preparing these alcoholic beverages arewell-known.

Production of Other AATases

As described above, the present invention provides the AATase geneencoding amino acid sequence from A to B of the amino acid sequenceshown in FIG. 1. (SEQ ID NO:15) According to another aspect of thepresent invention, the present invention provides other AATase genes. Ithas now been found that a different kind of AATase producing gene isobtained from a least gene library by use of a probe which is arelatively short DNA fragment of a DNA sequence encoding the amino acidsequence from A to B (SEQ ID NO:15) of the amino acid sequence shown inFIG. 1. It is interesting in this case that the probe originated fromthe DNA sequence obtained from a "sake" yeast provided two different DNAsequences having an AATase producing ability from the gene library of abrewery lager yeast. In addition, while both of these DNA sequences arecapable of producing AATase, the restriction maps, DNA sequences and theamino acid sequences of the DNA sequences are different from those ofthe amino acid sequence shown in FIG. 1 (SEQ ID NO:15) originated from asake yeast.

In the process of isolating these DNA sequences, a DNA fragment as aprobe is first provided. The probe has preferably a length of at least20 bases of the DNA sequence encoding a polypeptide having an amino acidfrom A to B (SEQ ID NO:15) of the amino acid sequence substantiallyshown in FIG. 1.

The length of the DNA strand as the probe is preferably at least 20bases, since sufficient hybridization will not occur with an excessivelyshort probe. The DNA strand has more preferably a length of 100 bases ormore.

The gene library to which the probe is applied preferably comprisesvectors containing DNA fragments having a substantially same length inthe range from 5×10³ bases to 30×10³ bases obtained by cutting achromosome of yeast by chemical or physical means such as restrictionenzyme or supersonic.

The restriction enzyme to be used in this procedure, of which the kindsand/or the reaction conditions should be set up so that for a certainyeast chromosome the DNA strands having a length within the above rangeare obtained. In case of making gene library from brewery yeastchromosommal DNA, suitable restriction enzymes include for exampleSau3AI or MboI.

It is desirable that the DNA fragment obtained by cutting havesubstantially the same length in the range from 5×10³ bases to 30×10³bases, in other words, the DNA fragment in the digested product withrestriction enzyme has uniform length within the range from 5×10³ basesto 30×10³ bases.

Cloning of the complementary DNA strands from the gene library usingprobes, and the subcloning of this cloned DNA fragments, for example,into the yeast is easily performed according to the well-known geneticengineering method (for example, Molecular Cloning, Cold Spring HarborLaboratory (1988)).

The amino acid sequence shown in FIG. 2 (SEQ ID NO:17) is a polypeptideencoded by one of the two DNA sequences obtained from the brewery lageryeast gene library by using a probe which has a sequence correspondingto the DNA sequence from 234 to 1451 shown in FIG. 1 (SEQ ID NO:14). Itis apparent from comparing the figures, the AATases originated frombrewery lager yeast and sake yeast, are different from each other onlyin 12 base pairs and 3 amino acids. The polypeptide having an amino acidsequence from A to B shown in FIG. 2 (SEQ ID NO:17) which was obtainedwith the hybridization/cloning method described above, can also beregarded as an equivalent polypeptide of the amino acid sequence from Ato B (SEQ ID NO:15) shown in FIG. 1, i.e., as a modified polypeptide inwhich some of amino acids have been deleted, substituted or added.

Similarly, the amino acid sequences (from A to C or from B to C) shownin FIG. 17 (SEQ ID NO:19 or residues 19-525 of SEQ ID NO:19) ispolypeptides encoded by the other DNA sequence obtained from the genelibrary of brewery larger yeast by using the some probe. It is apparentfrom comparing the figures, this AATase originated from brewery lageryeast is different from the AATase originated from sake yeast in 332base pairs and 102 amino acids.

EXAMPLES

The following examples are offered by way of illustration and are notintended to limit the invention any way. In the Examples, allpercentages are by weight unless otherwise mentioned.

(1) Preparation of AATase

The enzyme of the present invention can be obtained from the culture ofan microoprganism which is a member of Saccharomyces and produces anenzyme having the aforementioned properties. The preferred preparationprocess is as follows:

(1)-(i) Assay of AATase activity

A 1 ml of a solution containing a buffer for AATase reaction (25 mMimidazole hydrochloride buffer (pH 7.5 mM), 1 mM acetyl-CoA, 0.1% TritonX-100, 0.5% isoamyl alcohol, 1 mM dithiothreitol, 0.1M sodium chloride,20% glycerol: or 10 mM phosphate buffer (pH 7.5 mM), 1 mM acetyl-CoA,0.1% Triton X-100, 0.5% isoamyl alcohol, 1 mM dithiothreitol, 0.1Msodium chloride, 20% glycerol) and the enzyme of the present inventionwas encapsulated into a 20 ml vial and reacted at 25° C. for 1 hour.After incubation, the vial was opened and the reaction was stopped byadding 0.6 g of sodium chloride. n-Butanol was added as an internalstandard to the reaction mixture up to 50 ppm. The vial was capped witha teflon stopper. Then, the isoamyl acetate generated was determinedwith the head space gas chromatography (Shimadzu GC-9A, HSS-2A). underthe following condition:

Column: glass column 2.1 m×3 mm

Stationary phase: 10% Polyethylene Glycol 1540 Diasolid L (60/80 mesh)

Column temperature: 75° C.

Injection temperature: 150° C.

Carrier gas: nitrogen

Flow rate: 50 ml/min

Sample volume: 0.8 ml.

(1)-(ii) Preparation of crude enzyme

Yeast cells of KYOKAI No. 7 were inoculated in 500 ml of a YPD culture(1% yeast extract, 2% bactopeptone, glucose) and cultured at 15° C. for3 days. A 25 ml of the culture solution was inoculated into 1000 ml of aYPD culture medium in 20 set of Erlenmeyer flasks having a 200 ml volumeand cultured at 30° C. for 12 hours. Cells were then collected bycentrifugation (3,000 rpm, 10 min) and suspended into a buffer (50 mMTris hydrochloride buffer (pH 7.5 mM), 0.1M sodium sulfite, 0.8Mpotassium chloride) having a volume 10 times that of the cells. Afterthis, "ZYMOLYASE 100T" (yeast cell cleaving enzyme commerciallyavailable from SEIKAGAKU KOGYO K.K.; Japanese Patent No. 702095, U.S.Pat. No. 3,917,510) was added in an amount of 1/1,000 to the weight ofthe cells. The mixture was incubated with shaking at 30° C. for 1 hour.Then, the resulting protoplast was collected by centrifugation at 3,000rpm for 5 minutes, suspended in 400 ml of a buffer for the disruption ofcells (25 mM imidazole hydrochloride buffer (pH 7.5 mM), 0.6M potassiumchloride, 1 mM sodium ethylenediaminetetraacetate (EDTA)) and disruptedwith a microbe cell disrupting apparatus "POLYTRON PT10" (KINEMATICACo.). The cell debris were removed by centrifugation at 45,000 rpm togive a crude enzyme solution.

(1)-(iii) Preparation of microsome fraction

After the crude enzyme solution obtained in (1)-(ii) was centrifuged at100,000×G for 2 hours, and the resulting precipitate ("microsomalfraction") was suspended in 40 ml of a buffer (25 mM imidazolehydrochloride buffer (pH 7.5 mM), 1 mM dithiothreitol). When thesuspension was not immediately used, it was stored at -20° C.

(1)-(iv) Preparation of solubilized enzyme

After the microsomal fraction obtained in (1)-(iii) was placed in aErlenmeyer flask, Triton X-100 was added in an amount of 1/100 of thevolume. The mixture was gently agitated with a magnetic stirrer at 4° C.for 60 minutes so that the mixture was not foamed. The mixture was thencentrifuged at 100,000×G for 2 hours. The supernatant was then dialyzedovernight against the buffer A (25 mM imidazole hydrochloride buffer (pH7.2), 0.1% Triton X-100, 0.5% isoamyl alcohol, 1 mM dithiothreitol, 20%glycerol).

(1)-(v) Purification of enzyme

By repeating the procedures (1)-(ii) and (1)-(iii) twenty times,microsomal fraction was obtained and stored at -20° C. Then bysubjecting the procedure (1)-(iv) to the microsomal fraction, thesolubilized enzyme fraction for further purification was obtained. Thesolubilized enzyme fraction was first applied to a POLYBUFFER EXCHANGER94 column (Pharmacia) (adsorption: buffer A; elution: buffer A+agradient of 0.0 to 0.6M sodium chloride).

The active fraction was collected and repeatedly applied to thePOLYBUFFER EXCHANGER 94 column.

The active fraction was further purified in the manner as shown inTable 1. That is, the active fraction was purified by

(1) ion-exchange column chromatography with DEAE Toyopearl 55 (TOSOH,adsorption: buffer A; elution: buffer A+a gradient of 0.0 to 0.2M sodiumchloride);

(2) gel filtration chromatography with Toyopearl HW60 (TOSOH) usingbuffer B (10 mM phosphate buffer. (pH 7.5 mM), 0.1% Triton X-100, 0.5%isoamyl alcohol, 1 mM dithiothreitol, 0.1M sodium chloride, 20%glycerol); (3) hydroxyapatite column chromatography (Wako Pure ChemicalIndustries, Ltd., adsorption: buffer B; elution: buffer B+a gradient of10 to 50 mM phosphate buffer (pH 7.5 mM); or

(4) octyl sepharose column chromatography (Pharmacia, adsorption: 50 mMimidazole hydrochloride (pH 7.5 mM), 0.5% isoamyl alcohol, 1 mMdithiothreitol, 0.1M sodium chloride, 20% glycerol; solution: 50 mMimidazole hydrochloride (pH 7.5 mM), 0.1% Triton X-100, 0.5% isoamylalcohol, 1 mM dithiothreitol, 0.1M sodium chloride, 20% glycerol).

As shown in Table 1, AATase was purified approximately 2,000 times onthe basis of the specific activity. However, a small amount of otherproteins was still observed in SDS-PAGE with silver stain, thusindicating insufficient purification.

Thus, the present inventors have carried out affinity chromatographybased on the specific affinity between 1-hexanol and AATase. HexanolSepharose 4B column was prepared with 6-amino-1-hexanol (Wako PureChemical Industries, Ltd.) and CNBr activated Sepharose 4B (Pharmacia)as a support according to the protocol by Pharmacia. Affinitychromatography was conducted with the column (adsorption: 5 mM phosphatebuffer (pH 7.2), 0.1% Triton X-100, 20% glycerol, 1 mM dithiothreitol;elution: sodium chloride with a gradient from 0.0 to 0.2M). The activefraction thus obtained as shown in FIG. 9 was subjected to SDS-PAGE andstained wAATase was success AATase was successfully purified tohomogenity since the active fraction was an enzyme which afforded asingle band as shown in FIG. 8.

                  TABLE 1    ______________________________________    Purification of AATase    ______________________________________                                    Total               Volume      Activity activity               (ml)        (ppm/ml) (ppm)    ______________________________________    Solubilized enzyme               505         119      60100    PBE 94 1st.               395         77       30400    PBE 94 2nd 86          304      26100    DEAE Toyopearl               24          580      13900    Toyopearl HW60               24          708      17000    Hydroxy apatite               7.6         1020     7750    Octyl sepharose               1.0         2390     2390    ______________________________________                         Specific                         activity        Rate of                 Protein (ppm/mg    Yield                                         Purifi-                 (mg/ml) protein)   (%)  cation    ______________________________________    Solubilized enzyme                 5.43    22         100  1    PBE 94 1st.  0.515   150        51   7    PBE 94 2nd.  1.086   280        43   13    DEAE Toyopearl                 0.96    604        23   27    Toyopearl HW60                 0.262   2700       28   123    Hydroxy apatite                 0.119   8570       13   266    Octyl sepharose                 0.056   42700      4    1940    ______________________________________

(2) Properties of AATase

(2)-(i) Substrate specificity

According to studies of substrate specificity of AATase to various kindsof alcohol by using the aforementioned analytical apparatuses andmethods, AATase acts on a variety of alcohol having 1-5 carbon, atoms.AATase acts more efficiently on alcohols having higher number of carbonatoms. In addition, AATase acts more efficiently on straight chainalcohols rather than branched chain alcohols (FIG. 9).

(2)-(ii) Optimum pH and pH stability

In order to examine the effect of pH on the stability of the enzyme, theenzyme was maintained at respective pH of from pH 5 to 9 (pH 5-6:50 mMcitrate-phosphate buffer; pH 6-8: 50 mM phosphate buffer; pH 8-9: 50 mMTris-phosphate buffer) under the condition of 4° C. for 22 hours. Theenzyme activity was assayed at pH 7.5 mM with 0.2M disodium phosphateaccording to the method (1)-(i).

In order to evaluate the effect of pH on the activity of the enzyme, theenzyme activities were assayed at respective pH of from 5 to 9 (pH5-6:50 mM citrate-phosphate buffer; pH 6-8: 50 mM phosphate buffer; pH8-9: 50 mM Tris-phosphate buffer) according to the method (1)-(i).

The enzyme of the present invention was stable within the pH range from7.5 mM to 8.5. The optimum pH was 8.0.

(2)-(iii) Optimum temperature and thermal stability

In order to examine the effect of temperature on the activity of theenzyme, the enzyme activities were assayed at various temperaturesaccording to the method of (1)-(i).

In addition, after the enzyme incubated at each temperature for 30minutes, the enzyme activities were assayed according to the method of(1)-(i).

The optimum temperature was 25° C. The enzyme was stable at 4° C., butit was very unstable at a temperature of higher than 4° C..

(2)-(iv) Inhibition

For the examination of effects of various inhibitors on the enzymeactivity, enzyme assay was carried out in a reaction buffer described in(1)-(i) containing inhibitors (1 mM) shown in Table 2 according to themethod of (1)-(i). The results are shown in Table 2. The enzymeaccording to the present invention is believed to be an SH enzyme,because it was inhibited strongly by p-chloromercuribenzoic acid (PCMB)and dithiobis (2-nitrobenzoic acid) (DTNB).

                  TABLE 2    ______________________________________    Inhibitor           Relative     Inhibitor    Relative    (1 mM) activity (%) (1 mM)       activity (%)    ______________________________________    None   100          ZnCl.sub.2   12.7    KCl    98.6         MnCl.sub.2   53.3    MgCl.sub.2           86.2         HgCl.sub.2   0    CaCl.sub.2           87.7         SnCl.sub.2   52.0    BaCl.sub.2           73.7         TNBS*        16.8    FeCl.sub.3           54.5         PCMB*        0    CoCl.sub.2           37.6         DTNB*        0    CdCl.sub.2           3.1          PMSF*        70.2    NiCl.sub.3           22.3         1,10-phenanthroline                                     87.9    CuSO.sub.4           0    ______________________________________     *1 mM TNBS: Trinitrobenzenesulfonic acid,     0.1 mM PCMB: pChloromercuribenzoic acid     0.1 mM DTNB: Dithiobis(2nitrobenzoic acid)     1 mM PMSF: Phenylmethanesulfonyl fluoride.

(2)-(v) Effects of fatty acids on enzyme activity

Various fatty acids were added in an amount of 2 mM to the reactionbuffer of (1)-(i) to examine the effect of the fatty acids on the enzymeactivity. The activity was assayed according to the method (1)-(i). Theresults are shown in Table 3.

                  TABLE 3    ______________________________________    Influence of fatty acids on the enzyme activity    Fatty acid          Relative activity    (2 mM)              (%)    ______________________________________    None                    100    Myristic acid  C.sub.14 H.sub.28 O.sub.2                            60.5    Palmitic acid  C.sub.16 H.sub.32 O.sub.2                            88.1    Palmitoleic acid                   C.sub.16 H.sub.30 O.sub.2                            16.7    Stearic acid   C.sub.18 H.sub.36 O.sub.2                            80.5    Oleic acid     C.sub.18 H.sub.34 O.sub.2                            59.6    Linoleic acid  C.sub.18 H.sub.32 O.sub.2                            4.3    Linolenic acid C.sub.18 H.sub.30 O.sub.2                            32.0    ______________________________________

(3) Sequencing of partial amino acid sequence

Partial amino acid sequence was determined according to the methoddescribed by Iwamatsu (SEIKAGAKU, 63, 139 (1991)) using a polyvinylidenedifluoride (PVDF) membrane. The AATase prepared in (1)-(v) was dialyzedagainst 3 liter of 10 mM formic acid for 1 hour and then lyophilized.The lyophilized enzyme was suspended in a buffer for electrophoresis(10% glycerol, 2.5% SDS, 2% 2-mercaptoethanol, 62 mM Tris hydrochloridebuffer (pH 6.8)) and subjected to SDS-PAGE. Then, the enzyme waselectroblotted onto a PVDF membrane of 10 cm×7 cm ("ProBlot", AppliedBiosystems) using ZARTBLOT IIs model (ZARTRIUS Co.). The electroblottingwas carried out at 160 mA for 1 hour according to "Pretreatment methodof a sample in PROTEIN SEQUENCER (1)" edited by SHIMAZDU SEISAKUSHO.

PVDF-immobilized enzyme was then cut off and dipped into about 300 μl ofa buffer for reduction (6M guanidine hydrochloride-0.5M Trishydrochloride buffer (pH 3.5), 0.3% EDTA, 2% acetonitrile) with 1 mg ofdithiothreitol (DTT) and reduced under argon at 60° C. for about 1 hour.A solution of 2.4 mg of monoiodoacetic acid in 10 μl of 0.5N sodiumhydroxide was added. The mixture was then stirred in darkness for 20minutes. After the PVDF membrane was taken out and washed sufficientlywith 2% acetonitrile, the membrane was further stirred in 0.1% SDS for 5minutes. The PVDF membrane was next rinsed lightly with water, dippedinto 0.5% polyvinylpyrrolidone -40 -100 mM acetic acid and left standingfor 30 minutes. The PVDF membrane was washed thoroughly with water andcut into square chips having a side of about 1 mm. The chips were dippedinto a digestion buffer (8% acetonitrile, 90 mM Tris hydrochloridebuffer (pH 9.0)) and digested at room temperature for 15 hours after 1pmol of ACROMOBACTER PROTEASE I (Wako Pure Chemical Industries, Ltd.)was added. The digested products was separated by reverse phase highperformance liquid chromatography (model L6200, HITACHI) with a C8column (NIPPON MILIPORE, LTD; μ-Bondasphere 5C8, 300A, 2.1×150 mm) togive a dozen or so peptide fragments. The elution of the peptide wascarried using the solvent A (0.05% trifluoroacetic acid) with a lineargradient from 2 to 50% of the solvent B (2-propanol/acetonitrile (7:3)containing 0.02% trifluoroacetic acid) at a flow rate of 0.25 ml/min.The amino acid sequencing of the peptide fragments thus was conducted bythe automatic Edman degradation method with a vapor phase proteinsequencer model 470 (Applied Biosystems) according to manufacturer'sinstructions.

As a result, the following amino acid sequences were determined:

    __________________________________________________________________________    peak       1        Lys                   Trp                      Lys    peak       2 (SEQ ID NO: 1)                Lys                   Tyr                      Val                         Asn                            Ile                               Asp    peak       3 (SEQ ID NO: 2)                Lys                   Asn                      Gln                         Ala                            Pro                               Val                                  Gln                                     Gln                                        Glu                                           Cys                                              Leu    peak       4 (SEQ ID NO: 3)                Lys                   Gly                      Met                         Asn                            Ile                               Val                                  Val                                     Ala                                        Ser    peak       5 (SEQ ID NO: 4)                Lys                   Tyr                      Glu                         Glu                            Asp                               Tyr                                  Gln                                     Leu                                        Leu                                           Arg                                              Lys    peak       6 (SEQ ID NO: 5)                Lys                   Gln                      Ile                         Leu                            Glu                               Glu                                  Phe                                     Lys    Peak       7 (SEQ ID NO: 6)                Lys                   Leu                      Asp                         Tyr                            Ile                               Phe                                  Lys    Peak       8 (SEQ ID NO: 7)                Lys                   Val                      Met                         Cys                            Asp                               Arg                                  Ala                                     Ile                                        Gly                                           Lys    Peak       9 (SEQ ID NO: 8)                Lys                   Leu                      Ser                         Gly                            Val                               Val                                  Leu                                     Asn                                        Glu                                           Gln                                              Pro                                                 Glu                Tyr    peak       10 (SEQ ID NO: 9)                Lys                   Asn                      Val                         Val                            Gly                               Ser                                  Gln                                     Glu                                        Ser                                           Leu                                              Glu                                                 Glu                Leu                   Cys                      Ser                         Ile                            Tyr                               Lys    __________________________________________________________________________

(4) Cloning of DNA encoding AATase from sake yeast

(i) Preparation of sake yeast library

Yeast cells of KYOKAI No. 7 were grown in 1 liter of a YPD medium up toO.D. 600=10, collected and washed with sterilized water. The cells weresuspended in SCE solution (1M sorbitol, 0.125M EDTA, 0.1M trisodiumcitrate (pH 7), 0.75% 2-mercaptoethanol, 0.01% "ZYMOLYACE 100T"(SEIKAGAKU KOGYO K.K.) in a ratio of 2 ml of SCE solution per 1 g of thecells, incubated at 37° C. for about 2 hours and protoplastizedcompletely. The resulting protoplast was suspended in Lysis Buffer (0.5MTris hydrochloride buffer (pH 9), 0.2M EDTA, 3% sodium dodecyl sulfate(SDS)) in an ratio of 3.5 ml of the buffer per 1 g of the cells. Themixture was then stirred gently at 65° C. for 15 minutes to lyse thecells completely. After the lysis, the mixture was cooled to roomtemperature, a 10 ml of the mixture was cautiously placed on each of23.5 ml of 10%-40% sucrose density gradient solution (0.8M sodiumchloride, 0.02M Tris hydrochloride buffer (pH 8), 0.0M EDTA, 10%-40%sucrose) which had been previously prepared in HITACHIultracentrifugation tubes 40PA. It was centrifuged with a HITACHIULTRACENTRIFUGE SCP85H at 4° C. and 26,000 rpm for 3 hours. After thecentrifugation, the resulted solution was recovered with a graduatedpippete (komagome) in an amount of about 5 ml from the bottom of thetube. The DNA sample thus recovered was dialyzed overnight against 1liter of a TE solution.

The chromosomal DNA thus obtained was partially digested with Sau3AIaccording to the method by Frischauf et al. (Methods in Enzymology, 152,183, Academic Press, 1987), placed again on 10%-40% sucrose densitygradient solution and centrifuged at 20° C. and 25,000 rpm for 22 hours.After centrifugation, the ultracentrifugation tube was pierced at thebottom with a needle, and 0.5 ml of the density gradient solution wasfractionated in every sampling tube. A portion. of each fraction wassubjected to agarose gel electrophoresis to confirm the molecular weightof the chromosomal DNA. Then, the 15-20 kb DNA was collected andrecovered by ethanol precipitation.

The digested chromosomal DNA (1 μg) and the λ-EMBL3 vector (1 μg) of aλ-EMBL3/BamH1 vector kit (manufactured by STRATAGENE, purchased fromFUNAKOSHI) were ligated at 16° C. overnight. The ligation product waspackaged using a GIGAPACK GOLD (manufactured by STRATAGENE, purchasedfrom FUNAKOSHI). The ligation and packaging were conducted according tomanufacturer's instructions. The host strain P2392 of the λ-EMBL3 vectorkit was infected with a 50 μl of the packaged solution. One inoculationloop amount of P2392 was cultured in 5 ml of a TB culture medium (1%bactotriptone (DIFCO), 0.5% sodium chloride, 0.2% maltose, pH 7.4) at37° C. overnight. Then, 1 ml of the culture was inoculated into 50 ml ofa TB culture medium and cells were grown up to O.D. 600=0.5. After theculture fluid was cooled on an ice bath, the cells were collected bycentrifugation and suspended in 15 ml of an ice-cooled 10 mM magnesiumsulfate solution. To 1 ml of the cells were added 0.95 ml of an SMsolution (0.1M sodium chloride, 10 mM magnesium sulfate, 50 mM Trishydrochloride buffer (pH 7.5 mM), 0.01% gelatin) and 50 μl of thepackaging solution. The mixture was slightly stirred and kept at atemperature of 37° C. for 15 minutes. A 200 μl portion of the mixturewas added into 7 ml of a BBL soft agar culture medium (1% Tripticasepeptone (BBL), 0.5% sodium chloride, 0.5% agarose (Sigma)) which hadbeen maintained at a temperature of 47° C. The mixture was slightlymixed and overlaid for spreading on a BBL agar plate (1% Tripticasepeptone, 0.5% sodium chloride, 1.5% Bactoagar (DIFCO)) having a diameterof 15 cm.

The overlaid plate was incubated at a temperature of 37° C. for 8 hours.A pharge library which contains approximately 30,000 clones having yeastchromosmal DNA fragments, on 10 overlaid agar plates were thus obtained.

The library was transferred to a nylon membrane for cloning. Ahybridization transfer membrane (NEN) having a diameter of 15 cm wascontacted with the overlaid agar plate for about 2 minutes to preparetwo sets of the membranes on which the phages were transferred and 20sheets in total. The membranes were placed with the surface which hadbeen contacted with the agar plate up on a filter paper impregnated withan alkali denaturating solution (1.5M sodium chloride, 0.5N sodiumhydroxide) and left standing for about 5 minutes. The membranes werethen displaced on a filter paper impregnated with a neutralizingsolution (3M sodium acetate (pH 5.8)), left standing for about 5minutes, then dried at room temperature and further dried in vacuum at80° C. for 1 hour. The agar plate from which the library had beentransferred were stored at 4° C.

(ii) Synthesis and Labelling of probes

The following synthetic probes were prepared using, a DNA synthesizer"Model 380B" (manufactured by APPLIED BIOSYSTEMS) on the basis of thepartial amino acid sequence of Peak 5 and Peak 2 obtained in (3):##STR1##

All of the synthesis reagents such as phosphoamidite were purchased fromAPPLIED BIOSYSTEMS and were used according to manufacturer'sinstructions.

The synthetic DNA thus obtained was treated with 3 ml of an 28% aqueousammonia at 200° C. for 4 hours and then purified with an OligonucleotidePurification Cartriges manufactured by APPLIED BIOSYSTEMS.

The two synthetic probes were individually labelled with [γ-³² P]ATP(ca. 6000 Ci/mM). Each probe DNA (ca. 250 ng) was subjected to reactionin 200 μl of a reaction solution containing 10 units of T4polynucleotide kinase, 500 μCi of [γ-³² P]ATP and a phosphate buffer(0.1 mM spermidine, 0.1 mM EDTA, 10 mM magnesium chloride, 5 mM DTT, 50mM Tris hydrochloride (pH 7.6)) at 37° C. for 1 hour, and kept at atemperature of 70° C. for 10 minutes. Unincorporated [γ-³² P]ATP wasremoved by the purification with a DE52 manufactured by WATTMAN.

(iii) Cloning by plaque hybridization

The cloning by plaque hybridization was carried out by first, second andthird screenings as follows:

In the first screening, 20 sheets of the membrane on which the yeastlibrary prepared in (4)-(i) had been transferred were dipped into 200 mlof a hybridization solution (6×SSPE (1.08M sodium chloride, 0.06M sodiumphosphate, 6 mM EDTA, pH 7.4), 5×a Denhardt's solution (0.1%polyvinylpyrrolidone, 0.1% Ficoil, 0.1% bovine serum albumin), 0.5% SDS,10 μg/ml single strand salmon sperm DNA) and incubated forprehybridization at 60° C. for 3 hours.

The [γ-³² P]ATP labelled probe 5 prepared in (4)-(ii) was kept at 95° C.for 5 minutes and cooled with ice-water. The twenty sheets of theprehybrized membrane were dipped into a mixed solution of the denaturedprobe 5 and 400 ml of a hybridization solution and incubated gently at30° C. overnight to hybridize the membrane with the labelled probe 5.

The hybridization solution was discarded. In order to remove theexcessive probe 5 from the membrane, the membrane was shaken gently in400 ml of 2×SSC (0.3M sodium chloride, 0.3M sodium citrate) at 30° C.for 20 film and exposed at -80° C. overnight. As positive clonesminutes. The membrane was then contacted with a X-ray 49 plaques whichhad sensitized both of the two sheets were subjected to the secondscreening.

In the second screening, these plaques on the original agar plates werepicked with an aseptic Pasteur's pipette and suspended into 1 ml of SM.After A 1/1000 dilution of the suspension was prepared, 100 μl of theP2392 microbial solution was infected with a 100 μl portion of thedilution in the same manner as in the preparation of the library, mixedwith 3 ml of a BBL soft agar medium and overlaid on a BBL agar plateshaving a diameter of 9 cm . After plaques had appeared, 49 sets of twomembrane sheets to one clone were prepared in the same manner asdescribed in (3)-(iii). The same procedure as in the first screening wasrepeated with the [γ-³² P]ATP labelled probe 2 which had been preparedin (4)-(ii). Fifteen plaques as the positive clones were subjected tothe third screening.

In the third screening, using the [γ-³² P]ATP labelled probe 5, the sameprocedure as in the second screening screening was repeated. Finally, 14positive clones were obtained.

An overnight culture of E. coli P2392 in TB medium was concentrated fourtimes in TB medium containing 10 mM MgSO₄. Then 20 μl of each positiveclone which had been prepared in a concentration of 10⁹ to 10¹⁰plaque/ml was infected to 5 ml of this cell suspension. This infectedall suspension was kept at 37° C. for 15 minutes, then inoculated into50 ml of TB medium containing 10 mM MgSO₄ and cultured for 6 hours withshaking. Then, CCl₄ was added to the cell culture and the culture wasincubated with shaking at 37° C. for 30 minutes to lyse P2392 andcentrifuged at 10,000 rpm for 10 minutes to recover the supernatant.DNase (TAKARA SHUZO) and RNase (BERINGER-MANNHEIM) were added to thesupernatant up to 10 μg/ml, respectively. The mixture was then kept at37° C. for 30 minutes. After the polyethylene glycol solution (20%Polyethylene Glycol 6000, 2.5M sodium chloride) was added in an amountof 30 ml, the mixture was left standing at 4° C. overnight.Centrifugation was conducted at 10,000 rpm for 10 minutes. After thesupernatant was discarded, the precipitate was suspended in 3 ml of SM.EDTA (pH 7.5 mM) and SDS were added to the suspension up to 20 mM and0.1%, respectively. The mixture was kept then at 55° C. for 4 minutesfollowed by adding the phenol solution (phenol (25): chloroform (24):isoamyl alcohol (1)). The mixture was slowly stirred for 10 minutes,centrifuged 10,000 rpm for 10 minutes to recover the DNA layer (aqueouslayer). After this procedure was repeated again, 0.33 ml of 3 M sodiumacetate and 7.5 mM ml of ethanol were added to the aqueous layer, andthe mixture was stirred and left standing at -80° C. for 30 minutes.After the mixture was centrifuged at 10,000 rpm for 10 minutes, theprecipitate was rinsed with 70% ethanol, then remove 70% ethanol, andthe precipitate was dried up and dissolved in 500 μl of TE. Each of thephage DNAs thus obtained was cut with a variety of restriction enzymesand compared with each other by electrophoresis. Although the fourteenpositive clones appeared consist of not only those containing the wholeof the DNA sequence capable of producing AATase but those having partialdeletions, all of the clones were those which cloned the identical siteon the. yeast chromosome. The restriction map of 6.6 kb XbaI fragmentcontaining the whole length of the DNA sequence among these clones areshown in FIG. 3. The DNA sequencing was carried out according to thedideoxy method with a XbaI fragment which had been subcloned in pUC119(TAKARA SHUZO). The DNA sequence of the gene encoding AATase is shown inFIG. 1 (SEQ ID NO:14).

(5) Preparation of DNA encoding AATase from brewery lager yeast

Using the sake yeast AATase gene as a probe, a DNA strands hybridizedwith the sake yeast (KYOKAI No. 7) AATase gene were cloned from brewerylager yeast. The 1.6 kb HindIII (the range within the arrow) fragmentshown in FIG. 3 (50 ng) was reacted with 100 μCi of [α-³² P]dCTP (ca.3,000 Ci/mM) using a Multiprime Labelling Kit (AMERSHAM JAPAN K.K.).Cloning by plaque hybridization was performed with this reaction productas a probe and the brewery lager yeast library containing 30,000 phageclones prepared in the same manner as described in (4)-(i).Hybridization temperature was set at 50° C. The membranes were. gentlyincubated at 50° C. in 2×SSC for 30 minutes and in 0.2×SSC (0.03M sodiumchloride, 3 mM sodium citrate) for 30 minutes in order to remove theexcessive probes. In the first screening, 60 positive clones wereobtained. These positive plaques were subjected to the second screeningin the same manner as described in (4)-(iii). Hybridization was repeatedwith the same probe under the same condition as described above to give30 positive clones. DNA was extracted from these positive clones andsubjected to restriction analysis. The results shows that those positiveclones are two groups. The restriction maps of the insert DNA of thesetwo groups are quite different, thus it has been suggested these insertDNAs present on different locus of yeast chromosome. FIG. 6 show therestriction maps of the DNA fragment containing AATase 1 and 2. Theseclones are referred to hereinafter as "brewery yeast AATase 1 gene" and"brewery yeast AATase 2 gene", respectively.

The DNA sequences of the brewery yeast AATase 1 gene and the breweryyeast AATase 2 gene were determined in the same manner as described in(4)-(iii). The DNA sequences of the brewery yeast AATase 1 gene and thebrewery yeast AATase 2 gene are shown in FIGS. 2 (SEQ ID NO:16) and 17(SEQ ID NOS:12 and 13, respectively), respectively. The AATase 2 genewas a DNA fragment which produces a polypeptide having an AATaseactivity in either case of the DNA sequence from A to C or the DNAsequence from B to C.

(6) Preparation of a vector containing an AATase gene and cultivation ofa yeast transformed by the vector

(i) Construction of an expression vector for Saccharomyces cerevisiae

A 6.6 kb XbaI fragment (AAT-K7) of the sake yeast AATase gene obtainedin (4)-(iii) and shown in FIG. 3 was prepared. The fragment was clonedinto the NheI site of the yeast vector YEp13K containing the replicationorigin of the yeast 2 μm DNA and the yeast LEU2 gene as a marker toconstruct the expression vector YATK11 (FIG. 11). In the same manner, a6.6 kb XbaI fragment (AAT-1) of the brewery yeast AATase gene 1 obtainedin (5) and shown in FIG. 4 was cloned into the NheI site of YEp13K toconstruct the expression vector YATL1 (FIG. 12). In addition, a 5.6 kbBglII fragment (AAT-2) of the brewery yeast AATase gene 2 shown in FIG.4 was cloned into the BamHI site of YEp13K to construct the expressionvector YATL2 (FIG. 13).

(ii) Construction of an expression vector for sake yeast KYOKAI No. 9

Plasmid pUC4k (Pharmacia) containing a G418 resistant gene was cut withSalI. Then, the resulting fragment containing the G418 resistant genewas cloned into the SalI site of the YATK11 to construct a vector YATK11G for transfecting the AATase gene into sake yeast (FIG. 14).

(iii) Construction of an expression vector for brewery lager yeast

(iii-a) Preparation of G418 resistant marker

The 2.9 kb HindIII fragment containing PGK gene (Japanese PatentLaid-Open Publication No. 26548/1990) was cloned into pUC18 (TAKARASHUZO). Plasmid pUCPGK21 containing a PGK promoter and a terminator wasshown in FIG. 16.

G418 resistant gene was cloned from the plasmid pNEO (Pharmacia) intothe pUCPGK21 by the process described in FIG. 16 to construct pPGKneo2.

(iii-b) Construction of expression vectors

pPGKNEO2 was digested with SalI to generate the ca. 2.8 kb fragmentcontaining the PGK promoter, the G418 resistant gene and the PGKterminator. This fragment was then cloned into the Xhol site of YATL1 toconstruct YATL1 G (FIG. 15).

(7) Transformation of yeasts with AATase gene

In order to confirm that the cloned AATase genes in (4)-(iii) and (5)Produces AATase, yeast cells were transformed with these vectorsprepared in (6), and AATase activity of the transformants were measured.The transfection of the plasmid into Saccharomyces cereviciae TD4 (a,his, leu, ura, trp) was carried out according to the lithium acetatemethod (J. Bacteriol., 153, 163 (1983)) to give YATK11/TD4, YATL1/TD4and YATL2/TD4 (SKB105 strain).

The transformant of SAKE YEAST KYOKAI NO. 9 (SKB106 strain) was obtainedaccording to the following procedure. The strain, in to which theplasmid had been transfected by the lithium acetate method, was spreadonto YPD agar plates containing G418 (300 μl/ml). The plates wereincubated at 30° C. for 3 days. Colonies grown up were inoculated againin a YPD agar medium containing G418 (500 μg/ml) and cultured at 30° C.for 2 days to give the transformants.

YATL1 G was transfected into the strain 2155 of the brewery lager yeastAlfred Jorgensen Laboratory (Denmark) (AJL2155 strain) in the followingprocedure. The yeast was cultured with shaking in 100 ml of a YPD mediumat 30° C. until O.D. 600=16. Cells were collected, rinsed once withsterilized water, then rinsed once with 135 mM Tris buffer (pH 8.0) andsuspended in the same buffer so that the suspension had a microbialconcentration of 2×10⁹ cells/mi. To 300 μl of the suspension were added10 μg of YATL1G, 20 μg of calf thymus DNA (Sigma) as a carrier DNA andfinally 1200 μl of 35% PEG4000 (which had been subjected to sterilizedfiltration). The mixture was then stirred sufficiently. A 750 μl portionof the stirred fluid was poured into a cuvette for Gene Pulser (BIORAD)and subjected once to an electric pulse treatment under the conditionsof 1 μF and 1000 V. The cell suspension was transferred from the cuvetteto a 15 ml tube and left standing at 30° C. for 1 hour. The cells werecollected by centrifugation at 3,000 rpm for 5 minutes, suspended. in 1ml of a YPD medium and incubated at 30° C. for 4 hour. The cells werecollected, suspended in 600 μl of sterilized water. A 150 μl of thesuspension were spread onto YPD agar plates containing G418 (100 μg/ml).The plates were incubated at 30° C. for 3 days to obtain thetransformant SKB108.

The AATase activities of the transformant into which the AATase gene hadbeen transfected and the control strains were measured. An SD liquidmedium containing a leucine-free mixed amino, acid solution (0.65% yeastnitrogen base (amino acid free; DIFCO), 2% glucose) was used forcultivating transformants of Saccharomyces cerevisiae TD4; an YPD liquidmedium containing G418 (400 μg/ml) was used for cultivatingtransformants of sake yeast KYOKAI No. 9; a YPD medium containing G418(10 μg/ml) was used for cultivating transformants of brewery lager yeastAJL2155 strain. A 25 ml portion of the shaking culture product at 30° C.for about 16 hours was added to 1000 ml of the culture medium and theculture was incubated at 30° C. for 12 to 18 hours under staticconditions.

The preparation of a crude enzyme and the assay of its activity wereperformed according to the procedures described in (1)-(ii) and (1)-(i).Protein concentration was determined with a BIORAD PROTEIN ASSAY KIT(BIORAD) according to the instructions of its manual.

The results for the Saccharomyces cerevisiae TD4, the sake yeast KYOKAINo. 9 and the beer yeast AJL2155 are shown in Tables 4, 5 and 6,respectively. The results shows that the transformants of the presentinvention have AATase activities of 2 to 15 time higher than that of theuntransformed stain. This indicates that the AATase gene according tothe present invention facilely provides a strain which produces a largeamount of an acetate ester such as isoamyl acetate.

                  TABLE 4    ______________________________________                     Crude enzyme activity    Transformants    (ppm/mg protein)    ______________________________________    YEp13K/TD4       7.8    YATK11/TD4       84.0    YATL1/TD4        116.2    YATL2/TD4 (SKB105)                     50.6    ______________________________________

                  TABLE 5    ______________________________________                     Crude enzyme activity    Transformants    (ppm/mg protein)    ______________________________________    K9               3.4    YATK11G/K9 (SKB106)                     11.6    ______________________________________

                  TABLE 6    ______________________________________                       Crude enzyme activity    Transformants      (ppm/mg protein)    ______________________________________    AJL2155            4.1    YATK11G/AJL2155 (SKB108)                       11.6    ______________________________________

(8) Fermentation test of the transformants

Sake and beer were prepared by use of the yeast transformed with theAATase gene in the above (7).

(8)-(i) Production of sake with the transformant yeast

Small scale sake brewing test was carried out with 300 g rice accordingto the feed program as shown in Table 7. Thirty grams of malted rice(koji rice) and 110 ml of water including yeast (2×10⁷ cells/ml) (Kojirice) and lactic acid (0.35% (v/v)) were mixed and incubated at 15° C.On the second day, 35 g of steamed rice was added as the 1st feed. Onthe fourth day, the 2 nd feed was carried out. After fermentation for 15days, the fermentation product was centrifuged at 8,000 rpm for 30minutes. Esters concentration of the "sake" liquor was measured. Theresults are shown in Table 8. The liquor produced by the transformant ofthe present invention has an aromatic flavor due to an enhanced amountof acetate esters such as ethyl acetate, isoamyl acetate in comparisonwith the liquor produced by yeast cells of KYOKAI-K9.

                  TABLE 7    ______________________________________    Feed program for small scale sake brewing            Seed            Mash        1st        2nd       Total    ______________________________________    Steamed rice            35  g    213  g    248  g    Koji rice 30     g               22   g    52   g    Water     110    ml              310  ml   420  ml    ______________________________________

                  TABLE 8    ______________________________________               EtOH                Ethyl    Strain     (%)          NS     acetate    ______________________________________    YKB106     18.3         +12.1  38.8    K-9 (Control)               18.5         +12.3  16.6    ______________________________________                ISo     Isoamyl   Isoamyl                                        Ethyl    Strain      butanol alcohol   acetate                                        caproate    ______________________________________    YKB106      88.7    211.0     7.5   0.6    K-9 (Control)                93.3    230.9     4.4   0.5    ______________________________________     Unit: ppm     NS: Nippon Shudo (Sake degree)

(8)-(ii) Preparation of beer with transformant yeast

After yeast was added to the wort in which the original extract contentwas adjusted to 11° P., the mixture was incubated at 8° C. for 8 days,centrifuged at 3,000 rpm for 10 minutes and sterilized by filtration.Esters contained in the filtrated solution was measured. The results areshown in Table 9. The transformant of the present invention produced aliquor having an enhanced amount of acetate esters such as ethylacetate, isoamyl acetate in comparison with the liquor produced by theuntransformed yeast AJL2155.

                  TABLE 9    ______________________________________                Apparent                extract  Ethyl     Isoamyl                                         Isoamyl                content  acetate   acetate                                         alcohol    Strain      (°P)                         (ppm)     (ppm) (ppm)    ______________________________________    SKB108 (YATL1G)                2.3      22.8      0.99  51.2    AJL2155 (Control)                2.8      5.9       0.13  40.0    ______________________________________

(9) Preparation of DNA encoding AATase from the wine yeast

The primers A and B (SEQ ID NOS 12 and 13, respectively) which havehomology to two different sites in the sake yeast AATase gene shown inFIG. 6 were synthesized. Polymerase chain reaction (PCR) was performedwith Gene Amp Reagent Kit (TAKARA SHUZO) and DNA Thermal Cycler(Parkin-Elmer-Theters Instruments Co.) using chromosomal DNA of wineyeast as a template with the two primers to give a 1.17 kb DNA fragmentfrom the position of the primer A to the position of primer B. Theprocess consisted of 30 cycles with annealing at 50° C. for 2 minutes.The reaction mixture was applied to agarose electrophoresis. The 1.17 kbDNA fragment was purified from the gel, labelled with 100 μCi [³² P]dCTPusing Nick Translation Kit (TAKARA SHUZO) and hybridized with 20,000genome libraries of a wine yeast W-3 (YAMANASHI KOGYO GIJUTSU CENTER)prepared in the same manner as the sake yeast library. After thehybridization was carried out at 65° C., the membranes were rinsed with2×SSC (1×SSC is 15 mM NaCl plus 1.5 mM sodium citrate) for 20 minutes,2×SSC for 10 minutes and finally 0.1×SSC with gentle shaking at 65° C.As positive, 14 plaques were first obtained. Upon hybridizing theseplaques with the 1.7 kb fragment in the same manner as the above, 7positive plaques having a strong hybridization signal were obtained. Thephage DNAs of these positive plaques were purified and subjected torestriction enzyme analysis. As a result, it was found that all of the 7clones were of the same DNA having the restriction map shown in FIG. 5.

Deposition of the microorganisms

The microorganisms shown below related to the present invention havebeen deposited at Fermentation Research Institute of Agency ofIndustrial Science and Technology, Japan under the following depositionnumbers under the Budapest Treaty on the international Recognition ofthe Deposit of Microorganisms for the Purpose of Patent Procedure.

    ______________________________________    (1) SKB105         FERM BP-3828    (2) SKB106         FERM BP-3829    (3) SKB108         FERM BP-3830    ______________________________________

YATL2, YATK11 G and YATL1G can be obtained by culturing SKB105, SKB106and SKB108, respectively, under a certain condition, extractingtherefrom the total DNA of the yeast (Methods in yeast genetics, ColdSpring Harbor Laboratory, 1988), transforming Escherichia coli with thistotal DNA and finally extracting the plasmids by the alkali method (lit:Molecular clonign, Cold Spring Harbor Laboratory, 1989).

A DNA fragment containing a part of the DNA sequence from A to B (bases233-1808 of SEQ ID No:14 ) of the DNA sequence shown in FIG. 1 can beobtained by digesting YATK11G with an appropriate restriction enzyme. Anexample of a suitable DNA sequences is 1.6 kb HindIII fragment which isindicated by a double-headed arrow in FIG. 3.

    __________________________________________________________________________    SEQUENCE LISTING    (1) GENERAL INFORMATION:    (iii) NUMBER OF SEQUENCES: 19    (2) INFORMATION FOR SEQ ID NO:1:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 6 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:    LysTyrValAsnIleAsp    15    (2) INFORMATION FOR SEQ ID NO:2:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 11 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:    LysAsnGlnAlaProValGlnGlnGluCysLeu    1510    (2) INFORMATION FOR SEQ ID NO:3:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 9 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:    LysGlyMetAsnIleValValAlaSer    15    (2) INFORMATION FOR SEQ ID NO:4:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 11 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:    LysTyrGluGluAspTyrGlnLeuLeuArgLys    1510    (2) INFORMATION FOR SEQ ID NO:5:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 8 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:    LysGlnIleLeuGluGluPheLys    15    (2) INFORMATION FOR SEQ ID NO:6:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 7 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:    LysLeuAspTyrIlePheLys    15    (2) INFORMATION FOR SEQ ID NO:7:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 10 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:    LysValMetCysAspArgAlaIleGlyLys    1510    (2) INFORMATION FOR SEQ ID NO:8:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 13 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:8:    LysLeuSerGlyValValLeuAsnGluGlnProGluTyr    1510    (2) INFORMATION FOR SEQ ID NO:9:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 18 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:9:    LysAsnValValGlySerGlnGluSerLeuGluGluLeuCysSerIle    151015    TyrLys    (2) INFORMATION FOR SEQ ID NO:10:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 20 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:10:    AARTAYGARGARGAYTAYCA20    (2) INFORMATION FOR SEQ ID NO:11:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 17 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:11:    AARTAYGTNAAYATHGA17    (2) INFORMATION FOR SEQ ID NO:12:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 18 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:12:    CTCAATGAACAACCTGAG18    (2) INFORMATION FOR SEQ ID NO:13:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 18 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: single    (D) TOPOLOGY: linear    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:13:    TCTTCGAGAGATTCTTGG18    (2) INFORMATION FOR SEQ ID NO:14:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 1923 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: double    (D) TOPOLOGY: linear    (ix) FEATURE:    (A) NAME/KEY: CDS    (B) LOCATION: 234..1811    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:14:    AGCGTGTGAGGACTACTCATTGGCTTGCGATTTACGGTTTTTATATTTTTTGCCGCACAT60    CATTTTTTGGCCTGGTATTGTCATCGCGTTGAGCGGACTCTGAATATAATCCTATTGTTT120    TTTATGGATCTCTGGAAGCGTCTTTTTGAAGCCAACCCAACAAAAATTCGAGACAAGAAA180    ATAAAAAACGGCACTTCATCAGTATCACAAATACCATCAATTTATCAGCTCTCATG236    Met    AATGAAATCGATGAGAAAAATCAGGCCCCCGTGCAACAAGAATGCCTG284    AsnGluIleAspGluLysAsnGlnAlaProValGlnGlnGluCysLeu    51015    AAAGAGATGATTCAGAATGGGCATGCTCGGCGTATGGGATCTGTTGAA332    LysGluMetIleGlnAsnGlyHisAlaArgArgMetGlySerValGlu    202530    GATCTGTATGTTGCTCTCAACAGACAAAACTTATATCGGAACTTCTGC380    AspLeuTyrValAlaLeuAsnArgGlnAsnLeuTyrArgAsnPheCys    354045    ACATATGGAGAATTGAGTGATTACTGTACTAGGGATCAGCTCACATTA428    ThrTyrGlyGluLeuSerAspTyrCysThrArgAspGlnLeuThrLeu    50556065    GCTTTGAGGGAAATCTGCCTGAAAAATCCAACTCTTTTACATATTGTT476    AlaLeuArgGluIleCysLeuLysAsnProThrLeuLeuHisIleVal    707580    CTACCAATAAGATGGCCAAATCATGAAAATTATTATCGCAGTTCCGAA524    LeuProIleArgTrpProAsnHisGluAsnTyrTyrArgSerSerGlu    859095    TACTATTCACGGCCACATCCAGTGCATGATTATATTTCAGTATTACAG572    TyrTyrSerArgProHisProValHisAspTyrIleSerValLeuGln    100105110    GAATTGAAACTGAGTGGTGTGGTTCTCAATGAACAACCTGAGTACAGT620    GluLeuLysLeuSerGlyValValLeuAsnGluGlnProGluTyrSer    115120125    GCAGTAATGAAGCAAATATTAGAAGAATTCAAAAATAGTAAGGGTTCC668    AlaValMetLysGlnIleLeuGluGluPheLysAsnSerLysGlySer    130135140145    TATACTGCAAAAATTTTTAAACTTACTACCACTTTGACTATTCCTTAC716    TyrThrAlaLysIlePheLysLeuThrThrThrLeuThrIleProTyr    150155160    TTTGGACCAACAGGACCGAGTTGGCGGCTAATTTGTCTTCCAGAAGAG764    PheGlyProThrGlyProSerTrpArgLeuIleCysLeuProGluGlu    165170175    CACACAGAAAAGTGGAAAAAATTTATCTTTGTATCTAATCATTGCATG812    HisThrGluLysTrpLysLysPheIlePheValSerAsnHisCysMet    180185190    TCTGATGGTCGGTCTTCGATCCACTTTTTTCATGATTTAAGAGACGAA860    SerAspGlyArgSerSerIleHisPhePheHisAspLeuArgAspGlu    195200205    TTAAATAATATTAAAACTCCACCAAAAAAATTAGATTACATTTTCAAG908    LeuAsnAsnIleLysThrProProLysLysLeuAspTyrIlePheLys    210215220225    TACGAGGAGGATTACCAATTGTTGAGGAAACTTCCAGAACCGATCGAA956    TyrGluGluAspTyrGlnLeuLeuArgLysLeuProGluProIleGlu    230235240    AAGGTGATAGACTTTAGACCACCGTACTTGTTTATTCCGAAGTCACTT1004    LysValIleAspPheArgProProTyrLeuPheIleProLysSerLeu    245250255    CTTTCGGGTTTCATCTACAATCATTTGAGATTTTCTTCAAAAGGTGTC1052    LeuSerGlyPheIleTyrAsnHisLeuArgPheSerSerLysGlyVal    260265270    TGTATGAGAATGGATGATGTGGAAAAAACCGATGATGTTGTCACCGAG1100    CysMetArgMetAspAspValGluLysThrAspAspValValThrGlu    275280285    ATCATCAATATTTCACCAACAGAATTTCAAGCGATTAAAGCAAATATT1148    IleIleAsnIleSerProThrGluPheGlnAlaIleLysAlaAsnIle    290295300305    AAATCAAATATCCAAGGTAAGTGTACTATCACTCCGTTTTTACATGTT1196    LysSerAsnIleGlnGlyLysCysThrIleThrProPheLeuHisVal    310315320    TGTTGGTTTGTATCTCTTCATAAATGGGGTAAATTTTTCAAACCATTG1244    CysTrpPheValSerLeuHisLysTrpGlyLysPhePheLysProLeu    325330335    AACTTCGAATGGCTTACGGATATTTTTATCCCCGCAGATTGCCGCTCA1292    AsnPheGluTrpLeuThrAspIlePheIleProAlaAspCysArgSer    340345350    CAACTACCAGATGATGATGAAATGAGACAGATGTACAGATATGGCGCT1340    GlnLeuProAspAspAspGluMetArgGlnMetTyrArgTyrGlyAla    355360365    AACGTTGGATTTATTGACTTCACCCCATGGATAAGCGAATTTGACATG1388    AsnValGlyPheIleAspPheThrProTrpIleSerGluPheAspMet    370375380385    AATGATAACAAAGAAAAATTTTGGCCACTTATTGAGCACTACCATGAA1436    AsnAspAsnLysGluLysPheTrpProLeuIleGluHisTyrHisGlu    390395400    GTAATTTCGGAAGCTTTAAGAAATAAAAAGCACCTCCATGGCTTAGGG1484    ValIleSerGluAlaLeuArgAsnLysLysHisLeuHisGlyLeuGly    405410415    TTCAATATACAAGGCTTCGTTCAAAAATATGTGAATATTGACAAGGTA1532    PheAsnIleGlnGlyPheValGlnLysTyrValAsnIleAspLysVal    420425430    ATGTGCGATCGTGCCATCGGGAAAAGACGCGGAGGTACATTGTTAAGC1580    MetCysAspArgAlaIleGlyLysArgArgGlyGlyThrLeuLeuSer    435440445    AATGTAGGTCTGTTTAATCAGTTAGAGGAGCCCGATGCCAAATATTCT1628    AsnValGlyLeuPheAsnGlnLeuGluGluProAspAlaLysTyrSer    450455460465    ATATGCGATTTGGCATTTGGCCAATTTCAAGGATCCTGGCACCAAGCA1676    IleCysAspLeuAlaPheGlyGlnPheGlnGlySerTrpHisGlnAla    470475480    TTTTCCTTGGGTGTTTGTTCGACTAATGTAAAGGGGATGAATATTGTT1724    PheSerLeuGlyValCysSerThrAsnValLysGlyMetAsnIleVal    485490495    GTTGCTTCAACAAAAAATGTTGTTGGTAGCCAAGAATCTCTCGAAGAG1772    ValAlaSerThrLysAsnValValGlySerGlnGluSerLeuGluGlu    500505510    CTTTGCTCCATTTATAAAGCTCTCCTTTTAGGCCCTTAGATCTCAC1818    LeuCysSerIleTyrLysAlaLeuLeuLeuGlyPro    515520525    ATGATGCTTGACTGATATTATTCGACAATATGATTATGTCGTGTAAATAACCCACTTTCA1878    TGTTGTCACTCCCTCGGCTTTGGTTGGTTAAAGGGACTTATTGGT1923    (2) INFORMATION FOR SEQ ID NO:15:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 525 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:15:    MetAsnGluIleAspGluLysAsnGlnAlaProValGlnGlnGluCys    151015    LeuLysGluMetIleGlnAsnGlyHisAlaArgArgMetGlySerVal    202530    GluAspLeuTyrValAlaLeuAsnArgGlnAsnLeuTyrArgAsnPhe    354045    CysThrTyrGlyGluLeuSerAspTyrCysThrArgAspGlnLeuThr    505560    LeuAlaLeuArgGluIleCysLeuLysAsnProThrLeuLeuHisIle    65707580    ValLeuProIleArgTrpProAsnHisGluAsnTyrTyrArgSerSer    859095    GluTyrTyrSerArgProHisProValHisAspTyrIleSerValLeu    100105110    GlnGluLeuLysLeuSerGlyValValLeuAsnGluGlnProGluTyr    115120125    SerAlaValMetLysGlnIleLeuGluGluPheLysAsnSerLysGly    130135140    SerTyrThrAlaLysIlePheLysLeuThrThrThrLeuThrIlePro    145150155160    TyrPheGlyProThrGlyProSerTrpArgLeuIleCysLeuProGlu    165170175    GluHisThrGluLysTrpLysLysPheIlePheValSerAsnHisCys    180185190    MetSerAspGlyArgSerSerIleHisPhePheHisAspLeuArgAsp    195200205    GluLeuAsnAsnIleLysThrProProLysLysLeuAspTyrIlePhe    210215220    LysTyrGluGluAspTyrGlnLeuLeuArgLysLeuProGluProIle    225230235240    GluLysValIleAspPheArgProProTyrLeuPheIleProLysSer    245250255    LeuLeuSerGlyPheIleTyrAsnHisLeuArgPheSerSerLysGly    260265270    ValCysMetArgMetAspAspValGluLysThrAspAspValValThr    275280285    GluIleIleAsnIleSerProThrGluPheGlnAlaIleLysAlaAsn    290295300    IleLysSerAsnIleGlnGlyLysCysThrIleThrProPheLeuHis    305310315320    ValCysTrpPheValSerLeuHisLysTrpGlyLysPhePheLysPro    325330335    LeuAsnPheGluTrpLeuThrAspIlePheIleProAlaAspCysArg    340345350    SerGlnLeuProAspAspAspGluMetArgGlnMetTyrArgTyrGly    355360365    AlaAsnValGlyPheIleAspPheThrProTrpIleSerGluPheAsp    370375380    MetAsnAspAsnLysGluLysPheTrpProLeuIleGluHisTyrHis    385390395400    GluValIleSerGluAlaLeuArgAsnLysLysHisLeuHisGlyLeu    405410415    GlyPheAsnIleGlnGlyPheValGlnLysTyrValAsnIleAspLys    420425430    ValMetCysAspArgAlaIleGlyLysArgArgGlyGlyThrLeuLeu    435440445    SerAsnValGlyLeuPheAsnGlnLeuGluGluProAspAlaLysTyr    450455460    SerIleCysAspLeuAlaPheGlyGlnPheGlnGlySerTrpHisGln    465470475480    AlaPheSerLeuGlyValCysSerThrAsnValLysGlyMetAsnIle    485490495    ValValAlaSerThrLysAsnValValGlySerGlnGluSerLeuGlu    500505510    GluLeuCysSerIleTyrLysAlaLeuLeuLeuGlyPro    515520525    (2) INFORMATION FOR SEQ ID NO:16:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 1974 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: double    (D) TOPOLOGY: linear    (ix) FEATURE:    (A) NAME/KEY: CDS    (B) LOCATION: 346..1923    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:16:    GTAGCTTCATTTGTTGGCACAGGACTATTCCACCCTTAGAATTGACTTTTTGGACATTGA60    GCTAAGGTTCAATGCACTCGATGGTCTTCTCACTTCCGAATATATAGATCTAGCGTGTGA120    GGACTACTCATTGGCTTGCGATTTACGGTTTTTATATTTTTTGCCGCACATCATTTTTTG180    GCCTGGTATTGTCATCGCGGTTGAGCGGACTCTGAATATAATCCTATTGTTTTTTATGGA240    TCTCTGGAAGCGTCTTTTTGAAGCCAACCCAACAAAAATTCGAGACAAGAAAATAAAAAA300    CGGCACTTCATCAGTATCACAAATACCATCAATTTATCAGCTCTCATGAATGAA354    MetAsnGlu    1    ATCGATGAGAAAAATCAGGCCCCCGTGCAACAAGAATGCCTGAAAGAG402    IleAspGluLysAsnGlnAlaProValGlnGlnGluCysLeuLysGlu    51015    ATGATTCAGAATGGGCATGCTCGGCGTATGGGATCTGTTGAAGATCTG450    MetIleGlnAsnGlyHisAlaArgArgMetGlySerValGluAspLeu    20253035    TATGTTGCTCTCAACAGACAAAACTTATATCGAAACTTCTGCACATAT498    TyrValAlaLeuAsnArgGlnAsnLeuTyrArgAsnPheCysThrTyr    404550    GGAGAATTGAGTGATTACTGTACTAGGGATCAGCTCACATTAGCTTTG546    GlyGluLeuSerAspTyrCysThrArgAspGlnLeuThrLeuAlaLeu    556065    AGGGAAATCTGCCTGAAAAATCCAACTCTTTTACATATTGTTCTACCA594    ArgGluIleCysLeuLysAsnProThrLeuLeuHisIleValLeuPro    707580    ACAAGATGGCCAAATCATGAAAATTATTATCGCAGTTCCGAATACTAT642    ThrArgTrpProAsnHisGluAsnTyrTyrArgSerSerGluTyrTyr    859095    TCACGGCCACATCCAGTGCATGATTATATCTCAGTATTACAAGAATTG690    SerArgProHisProValHisAspTyrIleSerValLeuGlnGluLeu    100105110115    AAACTGAGTGGTGTGGTTCTCAATGAACAACCTGAGTACAGTGCAGTA738    LysLeuSerGlyValValLeuAsnGluGlnProGluTyrSerAlaVal    120125130    ATGAAGCAAATATTAGAAGAATTCAAAAATAGTAAGGGTTCCTATACT786    MetLysGlnIleLeuGluGluPheLysAsnSerLysGlySerTyrThr    135140145    GCAAAAATTTTTAAACTTACTACCACTTTGACTATTCCTTACTTTGGA834    AlaLysIlePheLysLeuThrThrThrLeuThrIleProTyrPheGly    150155160    CCAACAGGACCGAGTTGGCGGCTAATTTGTCTTCCAGAAGAGCACACA882    ProThrGlyProSerTrpArgLeuIleCysLeuProGluGluHisThr    165170175    GAAAAGTGGAGAAAATTTATCTTTGTATCTAATCATTGCATGTCTGAT930    GluLysTrpArgLysPheIlePheValSerAsnHisCysMetSerAsp    180185190195    GGTCGGTCTTCGATCCACTTTTTTCATGATTTAAGAGACGAATTAAAT978    GlyArgSerSerIleHisPhePheHisAspLeuArgAspGluLeuAsn    200205210    AATATTAAAACTCCACCAAAAAAATTAGATTACATTTTCAAGTACGAG1026    AsnIleLysThrProProLysLysLeuAspTyrIlePheLysTyrGlu    215220225    GAGGATTACCAATTATTGAGGAAACTTCCAGAACCGATCGAAAAGGTG1074    GluAspTyrGlnLeuLeuArgLysLeuProGluProIleGluLysVal    230235240    ATAGACTTTAGACCACCGTACTTGTTTATTCCGAAGTCACTTCTTTCG1122    IleAspPheArgProProTyrLeuPheIleProLysSerLeuLeuSer    245250255    GGTTTCATCTACAATCATTTGAGATTTTCTTCAAAAGGTGTCTGTATG1170    GlyPheIleTyrAsnHisLeuArgPheSerSerLysGlyValCysMet    260265270275    AGAATGGATGATGTGGAAAAAACCGATGATGTTGTCACCGAGATCATC1218    ArgMetAspAspValGluLysThrAspAspValValThrGluIleIle    280285290    AATATTTCACCAACAGAATTTCAAGCGATTAAAGCAAATATTAAATCA1266    AsnIleSerProThrGluPheGlnAlaIleLysAlaAsnIleLysSer    295300305    AATATCCAAGGTAAGTGTACTATCACTCCGTTTTTACATGTTTGTTGG1314    AsnIleGlnGlyLysCysThrIleThrProPheLeuHisValCysTrp    310315320    TTTGTATCTCTTCATAAATGGGGTAAATTTTTCAAACCATTGAACTTC1362    PheValSerLeuHisLysTrpGlyLysPhePheLysProLeuAsnPhe    325330335    GAATGGCTTACGGATATTTTTATCCCCGCAGATTGCCGCTCACAACTA1410    GluTrpLeuThrAspIlePheIleProAlaAspCysArgSerGlnLeu    340345350355    CCAGATGATGATGAAATGAGACAGATGTACAGATATGGCGCTAACGTT1458    ProAspAspAspGluMetArgGlnMetTyrArgTyrGlyAlaAsnVal    360365370    GGATTTATTGACTTCACCCCCTGGATAAGCGAATTTGACATGAATGAT1506    GlyPheIleAspPheThrProTrpIleSerGluPheAspMetAsnAsp    375380385    AACAAAGAAAATTTTTGGCCACTTATTGAGCACTACCATGAAGTAATT1554    AsnLysGluAsnPheTrpProLeuIleGluHisTyrHisGluValIle    390395400    TCGGAAGCTTTAAGAAATAAAAAGCATCTCCATGGCTTAGGGTTCAAT1602    SerGluAlaLeuArgAsnLysLysHisLeuHisGlyLeuGlyPheAsn    405410415    ATACAAGGCTTCGTTCAAAAATATGTGAACATTGACAAGGTAATGTGC1650    IleGlnGlyPheValGlnLysTyrValAsnIleAspLysValMetCys    420425430435    GATCGTGCCATCGGGAAAAGACGCGGAGGTACATTGTTAAGCAATGTA1698    AspArgAlaIleGlyLysArgArgGlyGlyThrLeuLeuSerAsnVal    440445450    GGTCTGTTTAATCAGTTAGAGGAGCCCGATGCCAAATATTCTATATGC1746    GlyLeuPheAsnGlnLeuGluGluProAspAlaLysTyrSerIleCys    455460465    GATTTGGCATTTGGCCAATTTCAAGGATCCTGGCACCAAGCATTTTCC1794    AspLeuAlaPheGlyGlnPheGlnGlySerTrpHisGlnAlaPheSer    470475480    TTGGGTGTTTGTTCGACTAATGTAAAGGGGATGAATATTGTTGTTGCT1842    LeuGlyValCysSerThrAsnValLysGlyMetAsnIleValValAla    485490495    TCAACAAAGAATGTTGTTGGTAGTCAAGAATCTCTCGAAGAGCTTTGC1890    SerThrLysAsnValValGlySerGlnGluSerLeuGluGluLeuCys    500505510515    TCCATTTACAAAGCTCTCCTTTTAGGCCCTTAGATCTCACATGATGCTTG1940    SerIleTyrLysAlaLeuLeuLeuGlyPro    520525    ACTGATATTATTCGACAATATGATTATGTCGTGT1974    (2) INFORMATION FOR SEQ ID NO:17:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 525 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:17:    MetAsnGluIleAspGluLysAsnGlnAlaProValGlnGlnGluCys    151015    LeuLysGluMetIleGlnAsnGlyHisAlaArgArgMetGlySerVal    202530    GluAspLeuTyrValAlaLeuAsnArgGlnAsnLeuTyrArgAsnPhe    354045    CysThrTyrGlyGluLeuSerAspTyrCysThrArgAspGlnLeuThr    505560    LeuAlaLeuArgGluIleCysLeuLysAsnProThrLeuLeuHisIle    65707580    ValLeuProThrArgTrpProAsnHisGluAsnTyrTyrArgSerSer    859095    GluTyrTyrSerArgProHisProValHisAspTyrIleSerValLeu    100105110    GlnGluLeuLysLeuSerGlyValValLeuAsnGluGlnProGluTyr    115120125    SerAlaValMetLysGlnIleLeuGluGluPheLysAsnSerLysGly    130135140    SerTyrThrAlaLysIlePheLysLeuThrThrThrLeuThrIlePro    145150155160    TyrPheGlyProThrGlyProSerTrpArgLeuIleCysLeuProGlu    165170175    GluHisThrGluLysTrpArgLysPheIlePheValSerAsnHisCys    180185190    MetSerAspGlyArgSerSerIleHisPhePheHisAspLeuArgAsp    195200205    GluLeuAsnAsnIleLysThrProProLysLysLeuAspTyrIlePhe    210215220    LysTyrGluGluAspTyrGlnLeuLeuArgLysLeuProGluProIle    225230235240    GluLysValIleAspPheArgProProTyrLeuPheIleProLysSer    245250255    LeuLeuSerGlyPheIleTyrAsnHisLeuArgPheSerSerLysGly    260265270    ValCysMetArgMetAspAspValGluLysThrAspAspValValThr    275280285    GluIleIleAsnIleSerProThrGluPheGlnAlaIleLysAlaAsn    290295300    IleLysSerAsnIleGlnGlyLysCysThrIleThrProPheLeuHis    305310315320    ValCysTrpPheValSerLeuHisLysTrpGlyLysPhePheLysPro    325330335    LeuAsnPheGluTrpLeuThrAspIlePheIleProAlaAspCysArg    340345350    SerGlnLeuProAspAspAspGluMetArgGlnMetTyrArgTyrGly    355360365    AlaAsnValGlyPheIleAspPheThrProTrpIleSerGluPheAsp    370375380    MetAsnAspAsnLysGluAsnPheTrpProLeuIleGluHisTyrHis    385390395400    GluValIleSerGluAlaLeuArgAsnLysLysHisLeuHisGlyLeu    405410415    GlyPheAsnIleGlnGlyPheValGlnLysTyrValAsnIleAspLys    420425430    ValMetCysAspArgAlaIleGlyLysArgArgGlyGlyThrLeuLeu    435440445    SerAsnValGlyLeuPheAsnGlnLeuGluGluProAspAlaLysTyr    450455460    SerIleCysAspLeuAlaPheGlyGlnPheGlnGlySerTrpHisGln    465470475480    AlaPheSerLeuGlyValCysSerThrAsnValLysGlyMetAsnIle    485490495    ValValAlaSerThrLysAsnValValGlySerGlnGluSerLeuGlu    500505510    GluLeuCysSerIleTyrLysAlaLeuLeuLeuGlyPro    515520525    (2) INFORMATION FOR SEQ ID NO:18:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 2080 base pairs    (B) TYPE: nucleic acid    (C) STRANDEDNESS: double    (D) TOPOLOGY: linear    (ix) FEATURE:    (A) NAME/KEY: CDS    (B) LOCATION: 311..1888    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:18:    CTTGAACATTGATCAATGTGAAATACTGATTGTGATGTTCAATATATTTGCTGATCTTAG60    GGTGATTGGTAACCAAAAATGCCGTCGGGCATTGTTCTAAAGGCTTGTGATTTTGTAAGT120    TTTTTGATCGCCTATTGTTTTTGGGCTGGCATCAGCATCGCGTGGAGCGAAGTCCAAATA180    TGTTTTCTATTGTTTTTCATGGCTCTTCGAGAAGCGTCTTTTTTAAAGCCAACCCAACAA240    AACTTGAGACATGGAAACAGAAGAAAGCCAATTTAGCAGTATAACAAAAATCATCAATCC300    AAAAACTCTAATGAATACCTACAGTGAAAAAACGTCTCTTGTTCAAGAT349    MetAsnThrTyrSerGluLysThrSerLeuValGlnAsp    1510    GAATGTCTTGTCAAGATGATACAGAATGGGCATTCCCGGCGTATGGGA397    GluCysLeuValLysMetIleGlnAsnGlyHisSerArgArgMetGly    152025    TCTGTGGAAGATTTGTACGCTGCACTCAACAGACAGAAATTGTATCGG445    SerValGluAspLeuTyrAlaAlaLeuAsnArgGlnLysLeuTyrArg    30354045    AATTTTTCGACATATTCAGAGCTGAATGATTACTGTACCAAAGATCAG493    AsnPheSerThrTyrSerGluLeuAsnAspTyrCysThrLysAspGln    505560    CTCGCATTAGCTCTAAGAAATATATGTTTGAAAAATCCGACTCTCCTA541    LeuAlaLeuAlaLeuArgAsnIleCysLeuLysAsnProThrLeuLeu    657075    CATATTGTATTACCGGCAAGATGGCCAGATCATGAAAAGTATTACCTT589    HisIleValLeuProAlaArgTrpProAspHisGluLysTyrTyrLeu    808590    AGCTCAGAATATTATTCACAGCCCCGTCCAAAACATGATTATATTTCG637    SerSerGluTyrTyrSerGlnProArgProLysHisAspTyrIleSer    95100105    GTTTTGCCTGAGTTGAAATTAGATGGTGTGATTCTCAACGAGCAACCT685    ValLeuProGluLeuLysLeuAspGlyValIleLeuAsnGluGlnPro    110115120125    GAGCACAATGCCCTAATGAAGCAAATACTAGAAGAATTTGCGAATAGC733    GluHisAsnAlaLeuMetLysGlnIleLeuGluGluPheAlaAsnSer    130135140    AATGGATCTTATACTGCAAAAATCTTTAAATTGACCACCGCTTTGACT781    AsnGlySerTyrThrAlaLysIlePheLysLeuThrThrAlaLeuThr    145150155    ATACCTTACACTGGGCCAACAAGTCCAACTTGGCGGTTGATTTGTCTC829    IleProTyrThrGlyProThrSerProThrTrpArgLeuIleCysLeu    160165170    CCAGAAGAAGATGACACGAATAAGTGGAAGAAATTTATATTTGTATCC877    ProGluGluAspAspThrAsnLysTrpLysLysPheIlePheValSer    175180185    AATCACTGCATGTGCGATGGTAGATCCTCAATTCACTTTTTTCAGGAT925    AsnHisCysMetCysAspGlyArgSerSerIleHisPhePheGlnAsp    190195200205    CTAAGAGATGAATTAAACAACATAAAAACTCTGCCAAAGAAATTGGAC973    LeuArgAspGluLeuAsnAsnIleLysThrLeuProLysLysLeuAsp    210215220    TACATTTTCGAGTACGAAAAGGATTACCAACTTTTGAGAAAGCTCCCA1021    TyrIlePheGluTyrGluLysAspTyrGlnLeuLeuArgLysLeuPro    225230235    GAACCCATTGAAAATATGATAGATTTCAGGCCGCCATATTTGTTTATT1069    GluProIleGluAsnMetIleAspPheArgProProTyrLeuPheIle    240245250    CCGAAGTCTCTTCTTTCTGGTTTTATTTACAGTCATTTGAGGTTTTCT1117    ProLysSerLeuLeuSerGlyPheIleTyrSerHisLeuArgPheSer    255260265    TCAAAGGGTGTTTGCACGAGAATGGATGAGATAGAAAAAAGTGATGAG1165    SerLysGlyValCysThrArgMetAspGluIleGluLysSerAspGlu    270275280285    ATTGTTACAGAAATTATCAATATTTCTCCATCAGAGTTTCAAAAAATT1213    IleValThrGluIleIleAsnIleSerProSerGluPheGlnLysIle    290295300    AGAACGAAAATTAAATTAAACATTCCCGGTAAGTGCACCATCACTCCG1261    ArgThrLysIleLysLeuAsnIleProGlyLysCysThrIleThrPro    305310315    TTCTTAGAAGTTTGTTGGTTTGTTACTCTCCATAAATGGGGCAAGTTT1309    PheLeuGluValCysTrpPheValThrLeuHisLysTrpGlyLysPhe    320325330    TTCAAACCACTGAAGTTCGAGTGGCTCACTGATGTTTTTATACCTGCA1357    PheLysProLeuLysPheGluTrpLeuThrAspValPheIleProAla    335340345    GATTGCCGCTCATTGCTGCCTGAAGATGAAGAAGTGAGAGCTATGTAC1405    AspCysArgSerLeuLeuProGluAspGluGluValArgAlaMetTyr    350355360365    AGGTACGGCGCTAACGTTGGGTTTGTTGACTTCACTCCATGGATAAGC1453    ArgTyrGlyAlaAsnValGlyPheValAspPheThrProTrpIleSer    370375380    AAATTCAACATGAACGACAGCAAAGAAAATTTCTGGCCACTTATTGCA1501    LysPheAsnMetAsnAspSerLysGluAsnPheTrpProLeuIleAla    385390395    CATTATCATGAAGTAATTTCCGGGGCGATAAAAGACAAGAAGCATCTC1549    HisTyrHisGluValIleSerGlyAlaIleLysAspLysLysHisLeu    400405410    AATGGTTTGGGGTTCAACATACAAAGCTTGGTCCAAAAGTATGTCAAC1597    AsnGlyLeuGlyPheAsnIleGlnSerLeuValGlnLysTyrValAsn    415420425    ATTGATAAAGTAATGCGTGATCGTGCTCTTGGTAAATCACGTGGGGGC1645    IleAspLysValMetArgAspArgAlaLeuGlyLysSerArgGlyGly    430435440445    ACTTTGTTGAGCAACGTAGGTATGTTCCACCAATCGGAGGAGACCGAA1693    ThrLeuLeuSerAsnValGlyMetPheHisGlnSerGluGluThrGlu    450455460    CACAAGTATCGTATAAGAGATTTGGCCTTTGGTCAATTTCAAGGGTCA1741    HisLysTyrArgIleArgAspLeuAlaPheGlyGlnPheGlnGlySer    465470475    TGGCATCAAGCTTTTTCATTGGGTGTTTCTTCGACTAATGTGAAGGGA1789    TrpHisGlnAlaPheSerLeuGlyValSerSerThrAsnValLysGly    480485490    ATGAACATTTTGATTTCTTCAACGAAAAATGTCGTGGGTAGTCAAGAA1837    MetAsnIleLeuIleSerSerThrLysAsnValValGlySerGlnGlu    495500505    TTGTTGGAGGAACTTTGTGCTATGTACAAGGCTCTGCTTTTAAATCCC1885    LeuLeuGluGluLeuCysAlaMetTyrLysAlaLeuLeuLeuAsnPro    510515520525    TGATTCTTCTAAGACAATATGATGGTGGATACCTTTAAAAATTATAGTTATATTGTAGGG1945    CTATCCTGTTTTGATATTATAATGTTTTTTTAGCTTGTAGAGAGAAATGGTATCAGTTTC2005    TTTTACTAAGATTCGAACTAATCAATATCTCAAAGTGATTAAACGACGTGTGTAAGGTAA2065    GTAAGTGTACAGAAA2080    (2) INFORMATION FOR SEQ ID NO:19:    (i) SEQUENCE CHARACTERISTICS:    (A) LENGTH: 525 amino acids    (B) TYPE: amino acid    (D) TOPOLOGY: linear    (ii) MOLECULE TYPE: protein    (xi) SEQUENCE DESCRIPTION: SEQ ID NO:19:    MetAsnThrTyrSerGluLysThrSerLeuValGlnAspGluCysLeu    151015    ValLysMetIleGlnAsnGlyHisSerArgArgMetGlySerValGlu    202530    AspLeuTyrAlaAlaLeuAsnArgGlnLysLeuTyrArgAsnPheSer    354045    ThrTyrSerGluLeuAsnAspTyrCysThrLysAspGlnLeuAlaLeu    505560    AlaLeuArgAsnIleCysLeuLysAsnProThrLeuLeuHisIleVal    65707580    LeuProAlaArgTrpProAspHisGluLysTyrTyrLeuSerSerGlu    859095    TyrTyrSerGlnProArgProLysHisAspTyrIleSerValLeuPro    100105110    GluLeuLysLeuAspGlyValIleLeuAsnGluGlnProGluHisAsn    115120125    AlaLeuMetLysGlnIleLeuGluGluPheAlaAsnSerAsnGlySer    130135140    TyrThrAlaLysIlePheLysLeuThrThrAlaLeuThrIleProTyr    145150155160    ThrGlyProThrSerProThrTrpArgLeuIleCysLeuProGluGlu    165170175    AspAspThrAsnLysTrpLysLysPheIlePheValSerAsnHisCys    180185190    MetCysAspGlyArgSerSerIleHisPhePheGlnAspLeuArgAsp    195200205    GluLeuAsnAsnIleLysThrLeuProLysLysLeuAspTyrIlePhe    210215220    GluTyrGluLysAspTyrGlnLeuLeuArgLysLeuProGluProIle    225230235240    GluAsnMetIleAspPheArgProProTyrLeuPheIleProLysSer    245250255    LeuLeuSerGlyPheIleTyrSerHisLeuArgPheSerSerLysGly    260265270    ValCysThrArgMetAspGluIleGluLysSerAspGluIleValThr    275280285    GluIleIleAsnIleSerProSerGluPheGlnLysIleArgThrLys    290295300    IleLysLeuAsnIleProGlyLysCysThrIleThrProPheLeuGlu    305310315320    ValCysTrpPheValThrLeuHisLysTrpGlyLysPhePheLysPro    325330335    LeuLysPheGluTrpLeuThrAspValPheIleProAlaAspCysArg    340345350    SerLeuLeuProGluAspGluGluValArgAlaMetTyrArgTyrGly    355360365    AlaAsnValGlyPheValAspPheThrProTrpIleSerLysPheAsn    370375380    MetAsnAspSerLysGluAsnPheTrpProLeuIleAlaHisTyrHis    385390395400    GluValIleSerGlyAlaIleLysAspLysLysHisLeuAsnGlyLeu    405410415    GlyPheAsnIleGlnSerLeuValGlnLysTyrValAsnIleAspLys    420425430    ValMetArgAspArgAlaLeuGlyLysSerArgGlyGlyThrLeuLeu    435440445    SerAsnValGlyMetPheHisGlnSerGluGluThrGluHisLysTyr    450455460    ArgIleArgAspLeuAlaPheGlyGlnPheGlnGlySerTrpHisGln    465470475480    AlaPheSerLeuGlyValSerSerThrAsnValLysGlyMetAsnIle    485490495    LeuIleSerSerThrLysAsnValValGlySerGlnGluLeuLeuGlu    500505510    GluLeuCysAlaMetTyrLysAlaLeuLeuLeuAsnPro    515520525    __________________________________________________________________________

What is claimed is:
 1. A process for isolating a DNA molecule encodingalcohol acetyltransferase (AATase), comprising the steps of:(a)preparing a DNA probe of at least 20 nucleotides which encodes a peptidefragment of the amino acid sequence of SEQ ID NO:15, and (b) screening aeukaryotic genomic library with said DNA probe to identify DNA moleculesencoding AATase.
 2. The method of claim 1, wherein said genomic libraryis prepared by cleaving genomic DNA using at least one enzyme or using aphysical means, wherein said cleavage produces DNA fragments havingabout 5×10³ nucleotides to about 30×10³ nucleotides.
 3. The method ofclaim 2, wherein said enzymatic cleavage is performed using Sau3AI orMboI.
 4. The method of claim 2, wherein said physical means issonication.
 5. The method of claim 1, wherein said DNA probe has thenucleotide sequence of either SEQ ID NO: 10 or SEQ ID NO:
 11. 6. Themethod of claim 1, wherein said DNA probe contains at least 20consecutive nucleotides of SEQ ID NO:14 from nucleotide 234 tonucleotide
 1808. 7. The method of claim 1, wherein said DNA probecontains at least 100 nucleotides that encode a peptide fragment of theamino acid sequence of SEQ ID NO:15.
 8. The method of claim 7, whereinsaid DNA probe is a fragment of a DNA molecule containing the nucleotidesequence of SEQ ID NO: 14.